Calibration of an electronics processing system

ABSTRACT

A first robot arm places a calibration object into a load lock that separates a factory interface from a transfer chamber using a first taught position. A second robot arm retrieves the calibration object from the load lock using a second taught position. A controller determines, using a sensor, a first offset amount between a calibration object center of the calibration object and a pocket center of the second robot arm. The controller determines a characteristic error value that represents a misalignment between the first taught position of the first robot arm and the second taught position of the second robot arm based on the first offset amount. The first robot arm or the second robot arm uses the first characteristic error value to compensate for the misalignment for objects transferred between the first robot arm and the second robot arm via the load lock.

RELATED APPLICATIONS

This patent application claims the benefit under 35 U.S.C. § 119(e) ofU.S. Provisional Application No. 62/991,016, filed Mar. 17, 2020.

TECHINCAL FIELD

Embodiments of the present disclosure relate, in general, to methods andsystems for calibrating components of an electronics processing system,and in particular to calibrating transfer sequences between componentsof an electronics processing system.

BACKGROUND

An electronics processing system may include one or more robot arms fortransporting a substrate from a first station of the electronicsprocessing system to a second station of the electronics processingsystem. In electronics processing systems, a substrate or an object isto be moved from the first station and placed at a target orientationand position at the second station. Frequently, one or more systemerrors associated with the first station, the second station and/or oneor more robot arms may prevent a robot arm from placing the substrate orthe object at a target orientation and position at the second station.For example, the electronics processing system may include an alignerstation and a processing chamber, where a substrate or object may beretrieved from the aligner station by a robot arm for transfer to theprocessing chamber at a target orientation. The aligner station and/orthe processing chamber may be associated with a characteristic errorresulting from a variety of sources (e.g., the aligner station and/orthe processing chamber was not installed properly during construction ofthe processing system, small errors in robot arm positioning and/ororientation, etc.). Accordingly, when the substrate or object istransferred from the aligner station and ultimately to the processingchamber, the substrate or object may have a small error in orientationand/or positioning.

SUMMARY

Some of the embodiments described cover a method of calibrating atransfer sequence between an aligner station and another station of anelectronics processing system. A calibration object is placed at atarget orientation in a station of an electronics processing device by afirst robot arm, and then retrieved from the station by the first robotarm. The calibration object is transferred to an aligner station usingthe first robot arm, a second robot arm and/or a load lock, wherein thecalibration object has a first orientation at the aligner station. Thefirst orientation at the aligner station is determined. A characteristicerror value is determined based on the first orientation. In oneembodiment, a difference between the first orientation and an initialtarget orientation at the aligner station is determined, wherein theinitial target orientation at the aligner station is associated with thetarget orientation in the first station, and the characteristic errorvalue is determined based on the difference between the firstorientation and the initial target orientation. The characteristic errorvalue is recorded in a storage medium. The aligner station is to use thecharacteristic error value for alignment of objects to be placed in thefirst station.

In some embodiments, a calibration object for an electronics processingsystem includes a body sized to fit through a slit valve of theelectronics processing system. The body includes a first plurality ofkinematic coupling interfaces in the body, the first plurality ofkinematic coupling interfaces being configured to engage with arespective first plurality of registration features of a first stationof the electronics processing system and to guide the calibration objectto a target position and a target orientation at the first station. Thebody further includes a fiducial disposed at a side of the body, whereinthe fiducial is usable to determine an orientation of the calibrationobject. The calibration object is configured to achieve a targetposition and/or orientation when placed into a station of theelectronics processing system, even when the calibration object isinitially placed at the station with an incorrect orientation and/orposition.

In some embodiments, an electronics processing system comprises atransfer chamber comprising a first robot arm, a plurality of processingchambers connected to the transfer chamber, a load lock connected to thetransfer chamber, a factory interface connected to the load lock, thefactory interface comprising a second robot arm and an aligner station,and a controller operatively connected to the first robot arm, thesecond robot arm and the aligner station. The controller is to cause thefirst robot arm or the second robot arm to retrieve a calibration objectfrom a first station of an electronics processing system, thecalibration object having a target orientation in the first station,wherein the first station is in a processing chamber of the plurality ofprocessing chambers, a side storage pod (SSP), the load lock, a loadport, or a front opening unified pod (FOUP). The controller is furtherto cause the calibration object to be transferred to the aligner stationusing at least one of the first robot arm, the second robot arm or theload lock, wherein the calibration object has a first orientation at thealigner station. The controller is further to determine the firstorientation at the aligner station. In one embodiment, the controllerdetermines a difference between the first orientation at the alignerstation and an initial target orientation at the aligner station,wherein the initial target orientation at the aligner station isassociated with the target orientation in the first station. Thecontroller is further to determine a first characteristic error valueassociated with the first station based on first orientation (e.g.,based on the difference between the first orientation and the initialtarget orientation). The controller is further to record the firstcharacteristic error value in a storage medium, wherein the alignerstation is to use the first characteristic error value for alignment ofobjects to be placed in the first station.

In some embodiments, a method includes placing, by a first robot arm ina first one of a factory interface or a transfer chamber, a calibrationobject into a load lock that separates the factory interface from thetransfer chamber, wherein the calibration object is placed into the loadlock such that a calibration object center is at a first target locationassociated with a first taught position of the first robot arm, whereina first pocket center of a first blade of the first robot arm nominallycorresponds to the first target location for the first taught position,and wherein the factory interface, the transfer chamber, and the loadlock are components of an electronics processing system. The methodfurther includes retrieving, by a second robot arm in a second one ofthe factory interface or the transfer chamber, the calibration objectfrom the load lock onto a second blade of the second robot arm using asecond taught position of the second robot arm, wherein a second pocketcenter of the second blade nominally corresponds to the first targetlocation for the second taught position, and wherein the calibrationobject center is offset from the second pocket center by a first offsetamount after retrieving the calibration object. The method furtherincludes determining, using a sensor that is in or connected to thesecond one of the factory interface or the transfer chamber, the firstoffset amount between the calibration object center and the secondpocket center. The method further includes determining a firstcharacteristic error value that represents a misalignment between thefirst taught position of the first robot arm and the second taughtposition of the second robot arm based on the first offset amount. Themethod further includes recording the first characteristic error valuein a storage medium, wherein one of the first robot arm or the secondrobot arm is to use the first characteristic error value to compensatefor the misalignment for objects transferred between the first robot armand the second robot arm via the load lock.

In some embodiments, an electronics processing system comprises a loadlock, a factory interface connected to a first side of the load lock, atransfer chamber connected to a second side of the load lock, and acontroller. The controller is to cause a first robot arm in a first oneof the factory interface or the transfer chamber to place a calibrationobject into the load lock, wherein the calibration object is to beplaced into the load lock such that a calibration object center is at afirst target location associated with a first taught position of thefirst robot arm, wherein a first pocket center of a first blade of thefirst robot arm nominally corresponds to the first target location forthe first taught position. The controller is further to cause a secondrobot arm in a second one of the factory interface or the transferchamber to retrieve the calibration object from the load lock onto asecond blade of the second robot arm using a second taught position ofthe second robot arm, wherein a second pocket center of the second bladenominally corresponds to the first target location for the second taughtposition, and wherein the calibration object center is offset from thesecond pocket center by a first offset amount after retrieving thecalibration object. The controller is further to determine, using asensor that is in or connected to the second one of the factoryinterface or the transfer chamber, the first offset amount between thecalibration object center and the second pocket center. The controlleris further to determine a first characteristic error value thatrepresents a misalignment between the first taught position of the firstrobot arm and the second taught position of the second robot arm basedon the first offset amount. The controller is further to record thefirst characteristic error value in a storage medium, wherein one of thefirst robot arm or the second robot arm is to use the firstcharacteristic error value to compensate for the misalignment forobjects transferred between the first robot arm and the second robot armvia the load lock.

In some embodiments, a non-transitory computer readable medium comprisesinstructions that, when executed by a processing device, cause theprocessing device to perform the operations of any of the abovediscussed methods.

BRIEF DESCRIPTION OF THE DRAWINGS

The present disclosure is illustrated by way of example, and not by wayof limitation, in the figures of the accompanying drawings in which likereferences indicate similar elements. It should be noted that differentreferences to “an” or “one” embodiment in this disclosure are notnecessarily to the same embodiment, and such references mean at leastone.

FIG. 1 is a top schematic view of an example electronic processingsystem, according to aspects of the present disclosure.

FIGS. 2A, 2B and 2C illustrate an example first orientation, an exampletarget orientation and position, and an example first position of anobject at a processing chamber, according to aspects of the presentdisclosure.

FIGS. 3A and 3B illustrate an example first orientation and an exampleinitial target orientation of an object at an aligner of an electronicsprocessing system, according to aspects of the present disclosure.

FIG. 4 illustrates a calibration of an aligner station of the exampleelectronics processing system, according to aspects of the presentdisclosure

FIG. 5A illustrates an example calibration object, according to aspectsof the present disclosure.

FIG. 5B illustrates an example calibration object, according to aspectsof the present disclosure.

FIGS. 5C-5D illustrate an example calibration object, according toaspects of the present disclosure.

FIGS. 5E-5F illustrate placement of an example calibration object at astation, according to aspects of the present disclosure.

FIG. 5G illustrates removal of the example calibration object from thestation of FIGS. 5A-5B, according to aspects of the present disclosure.

FIG. 6 is flow chart for a method of calibrating a transfer sequence ofan object between an aligner station and a processing chamber of anelectronic processing system, according to embodiments of the presentdisclosure.

FIG. 7A is flow chart for a method of using a calibrated transfersequence to transfer an object between an aligner station and aprocessing chamber of an electronic processing system, according toembodiments of the present disclosure.

FIG. 7B is flow chart for a method of using a calibrated transfersequence to transfer an object between an aligner station and aprocessing chamber of an electronic processing system, according toembodiments of the present disclosure.

FIG. 8 is flow chart for a method of calibrating a transfer sequence ofan object between an aligner station and an additional station of anelectronic processing system, according to embodiments of the presentdisclosure.

FIG. 9 is flow chart for a method of using a calibrated transfersequence to transfer an object between an aligner station and a secondstation of an electronic processing system, according to embodiments ofthe present disclosure.

FIG. 10 is flow chart for a method of determining an accuracy of atransfer sequence between an aligner station and a second station of anelectronic processing system, according to embodiments of the presentdisclosure.

FIG. 11 is flow chart for a method of determining whether a transfersequence is out of calibration, according to embodiments of the presentdisclosure.

FIG. 12 is flow chart for a method of calibrating taught positions oftwo robot arms that transfer objects to one another via a load lock,according to embodiments of the present disclosure.

FIG. 13 is flow chart for a method of determining whether taughtpositions of two robot arms that transfer objects to one another via aload lock are calibrated to one another, according to embodiments of thepresent disclosure.

FIG. 14 is an example computing device that may operate as a controllerfor an electronics processing system, in accordance with embodiments ofthe present disclosure.

DETAILED DESCRIPTION OF EMBODIMENTS

Embodiments described herein are related to methods and systems forcalibrating one or more components of an electronics processing system.The components that are calibrated may include one or more stations(e.g., an aligner station, a station of a processing chamber, a loadlock, a load port, a front opening unified pod (FOUP), a side storagepod (SSP), and so on) and/or one or more robot arms (e.g., of a factoryinterface robot and/or a transfer chamber robot). In embodiments,multiple components of the electronics processing system are calibratedto one another such that cumulative error by any of the multiplecomponents is eliminated or reduced. Some embodiments described hereincover calibration of a wafer transfer sequence between two stations(e.g., between an aligner station and a station of the processingchamber). Other embodiments described herein cover calibration of wafertransfer between two robot arms at a station (e.g., between two robotarms that transfer substrates to one another via a load lock).

In one embodiment, a calibration object, such as a calibration ring, acalibration disc, or a calibration wafer, is used to determine one ormore characteristic error values associated with a station (e.g., aprocessing chamber) of the electronics processing system. Thecharacteristic error value(s) may then be used to transfer objects(e.g., wafers, process kit rings, etc.) from other stations in theelectronics processing system to the station with the characteristicserror and/or from the station to the other stations. Characteristicerror values may be determined for some or all of the stations in theelectronics processing system. The characteristic error values ofmultiple stations may be combined to determine any angular and/orpositional changes that are to be made when transferring objects betweenthe multiple stations in some embodiments. For example, a firstcharacteristic error value may be determined for a first station, asecond characteristic error value may be determined for a secondstation, and the first and second characteristic error values may beadded together to determine a combined characteristic error value to usein transferring objects between the first and second stations.

In one embodiment, a calibration object is used to determinecharacteristic error values associated with stations. In someembodiments, the calibration object may be placed at a station (e.g., aprocessing chamber) at a target orientation and/or a target position. Afirst robot arm of a first robot (e.g., a transfer chamber robot) mayretrieve the calibration object and place the calibration object at aload lock of the electronics processing system. The calibration objectmay be retrieved, by a second robot arm of a second robot (e.g., afactory interface robot), from the load lock and placed at a firstorientation and/or a first position at an aligner station of theelectronics processing system. A difference between the firstorientation and an initial target orientation may be determined.Additionally, or alternatively, a difference between the first positionand an initial target position may be determined using the alignerstation. A first characteristic error value associated with the station(e.g., processing chamber) may be determined based on the differencebetween the first orientation and the initial target orientation. One ormore additional characteristic error values associated with the stationmay be determined based on the difference between the first position andthe initial target position. The characteristic error value(s) may bestored at a storage medium. After the characteristic error value orvalues are determined and stored at the storage medium, an object may bereceived at the aligner station to be processed at the station (e.g.,processing chamber). The characteristic error value(s) associated withthe processing chamber may be retrieved from the storage medium and theobject may be aligned to the initial target orientation and/or theinitial target position based on the characteristic error value, asmodified by the characteristic error value(s).

In one embodiment, a calibration object is used to determine and correctan offset between taught positions of two robot arms that transferobjects to one another via a load lock. The first robot arm may have afirst taught position at the load lock, and the second robot arm mayhave a second taught position at the load lock that should line up withthe first taught position. However, there is often some inaccuracy withregards to the taught positions. For example, the first robot arm (e.g.,of a factory interface robot) may be taught to place a substrate at theload lock such that a first pocket center of the first robot arm is at acenter of the load lock (center in the x-y plane). Thus, if thesubstrate has a center that lines up with the first pocket center whenthe substrate is placed in the load lock, the center of the substratewill correspond with the center of the load lock chamber. However, therobot arm may actually place the substrate at an offset from the centerof the load lock chamber. The same issue may occur for a second robotarm (e.g., of a transfer chamber robot), which may also be taught toplace a substrate at the load lock such that a second pocket center ofthe second robot arm is at the center of the load lock (center in thex-y plane).

To identify and correct for the offset between the taught positions ofthe first and second robot arms, in one embodiment a first robot armplaces a calibration object (e.g., a calibration wafer or a substrate)into a load lock, wherein the calibration object is placed into the loadlock such that a calibration object center is at a first target locationassociated with a first taught position of the first robot arm, whereina first pocket center of a first blade of the first robot arm nominallycorresponds to the first target location for the first taught position.A second robot arm retrieves the calibration object from the load lockonto a second blade of the second robot arm using a second taughtposition of the second robot arm, wherein a second pocket center of thesecond blade nominally corresponds to the first target location for thesecond taught position, and wherein the calibration object center isoffset from the second pocket center by a first offset amount afterretrieving the calibration object. A sensor (e.g., a local center finderor a sensor of an aligner station) is used to determine the first offsetamount between the calibration object center and the second pocketcenter. A first characteristic error value that represents amisalignment between the first taught position of the first robot armand the second taught position of the second robot arm based on thefirst offset amount is then determined. The first characteristic errorvalue is recorded in a storage medium. The first robot arm or secondrobot arm then uses the first characteristic error value to compensatefor the misalignment for objects transferred between the first robot armand the second robot arm via the load lock.

By calibrating the multiple components (e.g., wafer transfer sequencebetween multiple components) as described in embodiments herein prior toplacing objects (e.g., substrates, wafers, replaceable parts orcomponents, etc.) in a target station (e.g., a processing chamber), alikelihood that each object will be positioned at a target orientationand/or position at the processing chamber increases. By increasing thelikelihood that each object will be positioned at the target orientationand/or position, a number of alignment operations to be performed at thedestination station is reduced, decreasing overall system latency.Additionally, the accuracy of the orientation (e.g., yaw) and/orposition of placed objects is improved over conventional systems inembodiments, with an orientation accuracy as high +/−0.2°, +/−0.1°, or+/−0.01° in embodiments. Similarly, by reducing the number of alignmentoperations to be performed at the destination station (e.g., processingchamber), a likelihood that the object, or a robot arm placing theobject at the processing chamber, will be damaged as a result of anincorrect x-axis, y-axis, or yaw-axis motion decreases. Additionally,the amount of time that it takes to properly insert new substrates,wafers and/or replaceable parts (e.g., process kit rings) intodestination stations (e.g., processing chambers) may be reduced inembodiments by ensuring that the parts are inserted at a properorientation and/or position on a first attempt.

FIG. 1 is a top schematic view of an example electronics processingsystem 100, according to one aspect of the disclosure. Electronicsprocessing system 100 may perform one or more processes on a substrate102. Substrate 102 maybe any suitably rigid, fixed-dimension, planararticle, such as, e.g., a silicon-containing disc or wafer, a patternedwafer, a glass plate, or the like, suitable for fabricating electronicdevices or circuit components thereon.

Electronics processing system 100 may include a mainframe 104 and afactory interface 106 coupled to mainframe 104. Mainframe 104 mayinclude a housing 108 having a transfer chamber 110 therein. Transferchamber 110 may include one or more processing chambers (also referredto as process chambers) 114 a, 114 b, 116 a, 116 b, 118 a, 118 bdisposed therearound and coupled thereto. Processing chambers 114 a, 114b, 116 a, 116 b, 118 a, 118 b may be coupled to transfer chamber 110through respective ports 131, which may include slit valves or the like.

Note that an approximately square shaped mainframe having four sides(also referred to as facets) is shown, with multiple processing chambersconnected to each facet. However, it should be understood that a facetmay include a single processing chamber or more than two processingchambers coupled thereto. Additionally, the mainframe 104 may have othershapes, such as a rectangular shape (in which different facets may havedifferent lengths) or a radial shape with more than four facets (e.g.,with five, six, or more facets).

Processing chambers 114 a, 114 b, 116 a, 116 b, 118 a, 118 b may beadapted to carry out any number of processes on substrates 102. A sameor different substrate process may take place in each processing chamber114 a, 114 b, 116 a, 116 b, 118 a, 118 b. A substrate process mayinclude atomic layer deposition (ALD), physical vapor deposition (PVD),chemical vapor deposition (CVD), etching, annealing, curing,pre-cleaning, metal or metal oxide removal, or the like. In one example,a PVD process may be performed in one or both of process chambers 114 a,114 b, an etching process may be performed in one or both of processchambers 116 a, 116 b, and an annealing process may be performed in oneor both of process chambers 118 a, 118 b. Other processes may be carriedout on substrates therein. Processing chambers 114 a, 114 b, 116 a, 116b, 118 a, 118 b may each include a substrate support assembly. Thesubstrate support assembly may be configured to hold a substrate inplace while a substrate process is performed.

As described above, an etching process may be performed at one or moreprocessing chambers 114 a, 114 b, 116 a, 116 b, 118 a, 118 b. As such,some processing chambers 114 a, 114 b, 116 a, 116 b, 118 a, 118 b (suchas etch chambers) may include edge rings (also referred to as processkit rings) 136 that are placed at a surface of the substrate supportassembly. In some embodiments, the process kit rings may occasionallyundergo replacement. While replacement of process kit rings inconventional system includes disassembly of a processing chamber 114 a,114 b, 116 a, 116 b, 118 a, 118 b by an operator to replace the processkit ring, electronics processing system 100 may be configured tofacilitate replacement of process kit rings without disassembly of aprocessing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b by anoperator.

Transfer chamber 110 may also include a transfer chamber robot 112.Transfer chamber robot 112 may include one or multiple robot arms whereeach robot arm includes one or more end effectors (also referred toherein as blades) at the end of the robot arm. The end effector may beconfigured to handle particular objects, such as wafers. Alternatively,or additionally, the end effector may be configured to handle objectssuch as process kit rings. In some embodiments, transfer chamber robot112 may be a selective compliance assembly robot arm (SCARA) robot, suchas a 2 link SCARA robot, a 3 link SCARA robot, a 4 link SCARA robot, andso on.

In some embodiments, ports 131 and/or slit values are at interfacesbetween processing chambers 114 a, 114 b, 116 a, 116 b, 118 a, 118 b andtransfer chamber 110. Local center finders (LCFs) 150 are positioned ator proximate to each such port 131 or slit value. The local centerfinders 150 are each configured to determine a center of an object(e.g., a ring, wafer, substrate, etc.) passing through the associatedport 131 or slit value. LCFs 150 may include an arrangement of laser anddetector pairs. Each laser may project a laser beam, which may bereceived by a corresponding detector in a laser and detector pair. Inembodiments, the lasers direct the laser beams vertically or at an anglerelative to vertical. Each detector is positioned in the path of a laserbeam from a corresponding laser. When an object (e.g., a calibrationobject, a substrate, a wafer, etc.) is passed through the port 131 orslit valve, it blocks the laser beams such that the laser beams are notreceived by the detectors. Based on known information about a size andshape of the calibration object or other object passing through the port131 or slit valve, known information about positions of the lasers anddetectors, and known information about respective positions of thetransfer chamber robot 112 at which each of the respective detectorsstopped receiving a laser beam, a center of the calibration object orother known object may be determined. Other types of LCFs may also beused, such as camera-based local center finders and/or runoutribbon-based local center finders.

One or more load locks 120 a, 120 b may also be coupled to housing 108and transfer chamber 110. Load locks 120 a, 120 b may be configured tointerface with, and be coupled to, transfer chamber 110 on one side andfactory interface 106 on another side. Load locks 120 a, 120 b may havean environmentally-controlled atmosphere that may be changed from avacuum environment (wherein substrates may be transferred to and fromtransfer chamber 110) to an at or near atmospheric-pressure (e.g., withinert-gas) environment (wherein substrates may be transferred to andfrom factory interface 106) in some embodiments. In some embodiments,one or more load locks 120 a, 120 b may be a stacked load lock havingone or more upper interior chambers and one or more lower interiorchambers that are located at different vertical levels (e.g., one aboveanother). In some embodiments, a pair of upper interior chambers areconfigured to receive processed substrates from transfer chamber 110 forremoval from mainframe 104, while a pair of lower interior chambers areconfigured to receive substrates from factory interface 106 forprocessing in mainframe 104. In some embodiments, one or more load locks120 a, 120 b may be configured to perform a substrate process (e.g., anetch or a pre-clean) on one or more substrates 102 received therein.

In embodiments, ports 133 and/or slit valves separate the transferchamber 110 from the load locks 120 a, 120 b. LCFs 152 are positioned ator proximate to each such port 133 and/or slit value. The LCFs may beused to determine a center of objects (e.g., calibration objects,wafers, substrates, etc.) on robot arm 112 while such objects are placedin the load lock or removed from the load lock by the robot arm 112.

Factory interface (FI) 106 may be any suitable enclosure, such as, e.g.,an Equipment Front End Module (EFEM). Factory interface 106 may beconfigured to receive substrates 102 from substrate carriers 122 (e.g.,Front Opening Unified Pods (FOUPs)) docked at various load ports 124 offactory interface 106. A factory interface robot 126 (shown dotted) maybe configured to transfer substrates 102 between substrate carriers(also referred to as containers) 122 and load lock 120. Factoryinterface robot 126 may include one or more robot arms and may be orinclude a SCARA robot. In some embodiments, factory interface robot 126may have more links and/or more degrees of freedom than transfer chamberrobot 112. Factory interface robot 126 may include an end effector on anend of each robot arm. The end effector may be configured to pick up andhandle specific objects, such as wafers. Alternatively, or additionally,the end effector may be configured to handle objects such as process kitrings.

Any conventional robot type may be used for factory interface robot 126.Transfers may be carried out in any order or direction. Factoryinterface 106 may be maintained in, e.g., a slightly positive-pressurenon-reactive gas environment (using, e.g., nitrogen as the non-reactivegas) in some embodiments.

In some embodiments, a side storage pod (SSP, not shown) is coupled tothe FI 106.

The substrate carriers 122 as well as load ports 124, substrate carriers122, load locks 120 a, 120 b, SSPs, and processing chambers 114 a, 114b, 116 a, 116 b, 118 a, 118 b are each considered to be or includestations herein. Another type of station is an aligner station 128. Insome embodiments, transfer chamber 110, process chambers 114 a, 114 b,116 a, 116 b, and 118 a, 118 b, and load lock 120 may be maintained at avacuum level. Electronics processing system 100 may include one or moreports 130, 131, 133 (e.g., vacuum ports) that are coupled to one or morestations of electronics processing system 100. For example, ports 130(e.g., vacuum ports) may couple factory interface 106 to load locks 120.Additional ports 133 (e.g., vacuum ports) may be coupled to load locks120 and disposed between load locks 120 and transfer chamber 110, asdiscussed above. Each of the ports 130, 133, 131 may include slit valvesthat separate a vacuum environment from a higher pressure (e.g.,atmospheric pressure) environment.

In some embodiments, an aligner station 128 is coupled to FI 106.Alternatively, aligner station 128 may be housed in FI 106. A portseparates aligner station 128 from the FI 106 in some embodiments.Aligner station 128 is configured to align substrates, fixtures, and/orother objects (e.g., process kit rings) to a target orientation. Alignerstation 128 includes a substrate support onto which an object can beplaced. Once an object is placed on the substrate support, the substratesupport and object placed thereon are rotated, and an initialorientation on the aligner station and a target orientation on thealigner station may be detected based on such orientation.

In one embodiment, the aligner station 128 includes one or more pairs oflasers and detectors (e.g., a line of laser and detector pairs). Thelaser(s) may each project a laser beam that is vertical or at an angleto vertical. Each detector may be in a path of a laser beam, and detectsthe laser beam when the laser beam is received by the detector. As thesupported object (e.g., a calibration object, a substrate, a wafer,etc.) is rotated, one or more of the laser beams is interrupted by theobject such that it is not received by a detector for each rotationsetting. This information may be used to determine a distance between anedge of the object at a particular location that interrupted the one ormore laser beams and a center of the aligner station for each rotationsetting of the aligner station. Each object includes a fiducial such asa flat, a notch, a projection, etc. that can be detected by the alignerstation. For example, as the object is rotated, the distance between theedge of the object and the center of the aligner station may bedetermined for each rotation setting, and a known shape of the fiducialmay be used to identify the fiducial in the object from the determineddistances. Once the rotation setting associated with the fiduciallocation is identified, the phase of the object can be determined. Thisinformation can be used to determine a target orientation of the objectas well as an initial orientation that the object had when it was placedat the aligner station 128. Additionally, aligner station 128 may detectrunout of a circular object placed off center from a center of thealigner station based on the detected phase of the object and thedistances between the edge of the object and the center of the alignerstation for each rotation setting. Other detection mechanisms may alsobe used to detect orientation and/or runout of objects at the alignerstation.

Electronics processing system 100 may also include a system controller132. System controller 132 may be and/or include a computing device suchas a personal computer, a server computer, a programmable logiccontroller (PLC), a microcontroller, and so on. System controller 132may include one or more processing devices, which may be general-purposeprocessing devices such as a microprocessor, central processing unit, orthe like. More particularly, the processing device may be a complexinstruction set computing (CISC) microprocessor, reduced instruction setcomputing (RISC) microprocessor, very long instruction word (VLIW)microprocessor, or a processor implementing other instruction sets orprocessors implementing a combination of instruction sets. Theprocessing device may also be one or more special-purpose processingdevices such as an application specific integrated circuit (ASIC), afield programmable gate array (FPGA), a digital signal processor (DSP),network processor, or the like. System controller 132 may include a datastorage device (e.g., one or more disk drives and/or solid statedrives), a main memory, a static memory, a network interface, and/orother components. System controller 132 may execute instructions toperform any one or more of the methodologies and/or embodimentsdescribed herein. The instructions may be stored on a computer readablestorage medium, which may include the main memory, static memory,secondary storage and/or processing device (during execution of theinstructions). System controller 132 may also be configured to permitentry and display of data, operating commands, and the like by a humanoperator.

In some embodiments, system controller 132 causes electronics processingsystem 100 to perform one or more calibration procedures to generatecalibration data (e.g., characteristic error values) associated with oneor more stations, one or more robots and/or one or more wafer transfersequences. System controller 132 stores the calibration values (e.g.,characteristic error values) in one or more data storage devices. Systemcontroller 132 later uses appropriate calibration values wheninstructing the aligner station 128 to align an object, when instructingthe FI robot 126 to retrieve or place an object and/or when instructingthe transfer chamber robot 112 to retrieve or place an object.

FIG. 1 schematically illustrates transfer of an edge ring (or otherprocess kit ring) 136 into a processing chamber 114 a, 114 b, 116 a, 116b, 118 a, 118 b. However, it should be understood that other objectsother than edge rings may also be transferred using the same techniquesthat are described with reference to edge rings. Accordingly, it shouldbe understood that embodiments described with reference to edge ringsalso apply to substrates, cover wafers, multi-purpose wafers,calibration objects, replaceable parts other than edge rings, testwafers, and so on.

According to one aspect of the disclosure, an object such as an edgering 136 is removed from a substrate carrier 122 (e.g., a FOUP) or SSPvia factory interface robot 126 located in the factory interface 106, oralternatively, is loaded directly into the factory interface 106. Insome embodiments, system controller 132 determines a transfer recipe forthe object (e.g., edge ring 136). The transfer recipe may indicate atransfer path that the object (e.g., edge ring 136) is to follow whilebeing transported from substrate carrier 122 or SSP to a particularprocessing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b. Forexample, the transfer recipe may indicate that the object (e.g., edgering 136) is to be moved from aligner station 128 to a particular loadlock 120 a, 120 b to processing chamber 116 a, 116 b.

As discussed above, aligner station 128 is configured to align an objectsuch as edge ring 136 to achieve a target orientation of the object(e.g., edge ring 136) at a destination station (e.g., at a processingchamber 114 a, 114 b, 116 a, 116 b, or 118 a, 118 b). Aligner station128 may rotate the object (e.g., edge ring 136) in a positive ornegative yaw-axis direction (e.g., clockwise or counterclockwise) toachieve an initial target orientation of the object (e.g., edge ring136) at aligner station 128. In some embodiments, aligner station 128may additionally or alternatively translate the object (e.g., edge ring136) in a positive or negative x-axis and/or y-axis direction to alignthe object (e.g., edge ring 136) at aligner station 128. In someembodiments, an x-direction offset and/or a y-direction offset of theobject may be determined, and the offset(s) may be used to pick up theobject such that a center of the object corresponds to a center of apocket in a blade of the robot arm of the FI robot 126.

The initial target orientation of object (e.g., edge ring 136) ataligner station 128 may nominally correspond with a target orientationof the object (e.g., edge ring 136) at a destination station (e.g., atprocessing chamber 114 a, 114 b, 116 a, 116 b, or 118 a, 118 b). Forexample, edge ring 136 may include a flat that is to be aligned with acorresponding flat in a substrate support assembly around which the edgering 136 is to be placed in a processing chamber. Failure to accuratelyplace the edge ring 136 at the target orientation in the processingchamber may result in non-uniformities in generated plasma duringprocessing, in uneven wear of the edge ring 136, and/or other problems.In an ideal setup, with no robot position and/or rotation error, nomisadjustment of a processing chamber relative to the transfer chamber,etc., edge rings aligned to the initial target orientation at thealigner station should be orientated such that they will ultimately havea target orientation in any processing chamber once placed in thatprocess chamber. However, different robot errors may occur for placementof edge ring 136 in each of the processing chambers. Additionally, oneor more of the processing chambers may have a slight misalignment ormisadjustment.

Embodiments described herein provide a calibration procedure thatcorrects for any such robot errors, misalignments and/or misadjustments,as is described more fully below.

In one embodiment, the factory interface robot 126 positions the object(e.g., edge ring 136) at a first orientation at aligner station 128.System controller 132 may determine, based on a transfer recipe for theobject (e.g., edge ring 136), an alignment recipe to be performed ataligner station 128 to align the object (e.g., edge ring 136) to acorrected target orientation and/or a corrected target position. Thecorrected target orientation may correspond to an initial targetorientation at a source station (e.g., at the aligner station 128) asadjusted by a characteristic error value (e.g., a characteristic angularerror) associated with the transfer recipe. Similarly, the correctedtarget position may correspond to an initial target position at a sourcestation (e.g., at aligner station) as adjusted by a characteristic errorvalue (e.g., a characteristic positional error) associated with thetransfer recipe. In one embodiment, the characteristic error value(s)are associated with a particular processing chamber. In one embodiment,the characteristic error value(s) are associated with a particularprocessing chamber plus a particular load lock chamber. In oneembodiment, the characteristic error value(s) are associated with aparticular transfer sequence for moving the object from a source station(e.g., the aligner station 128) to a destination station (e.g.,processing chamber 116 a, 116 b). The alignment recipe may include thecharacteristic error value(s). In some embodiments, the aligner station128 aligns the object (e.g., edge ring 136) according to the alignmentrecipe, which may include moving the object (e.g., edge ring 136) in atleast one a positive or negative x-axis direction, a positive ornegative y-axis direction, and/or a positive or negative yaw-axisdirection (rotation) to properly orient and/or position the object(e.g., edge ring 136) to the corrected target orientation and/or to acorrected position at the aligner station 128. The alignment recipe maybe associated with the transfer recipe for the object (e.g., edge ring136). In response to aligning of the object (e.g., edge ring 136) ataligner station 128, factory interface robot 126 may then retrieve theobject (e.g., edge ring 136) from the aligner station 128, the retrievedobject (e.g., edge ring 136) having the corrected target orientation,and place the object into load lock 120 b through a port 130 with thecorrected orientation.

Transfer chamber robot 112 may remove object (e.g., edge ring 136) fromload lock 120 b through second vacuum port 130 b. Transfer chamber robot112 may move the object (e.g., edge ring 136) into the transfer chamber110, where the object may be transferred to a destination station (e.g.,processing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b). The object(e.g., edge ring 136) placed in the destination station (e.g.,processing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b) may havethe target orientation and/or the target position in destinationstation. Had the object been oriented to the initial target orientationin the aligner station 128, then the object would ultimately have hadthe characteristic error when placed at the destination station (e.g.,processing chamber). However, since the object was orientated to thecorrected target orientation in the aligner station (which may includethe initial target orientation minus an angular adjustment correspondingto the characteristic error value), the object placed in the processingchamber has the target orientation in the processing chamber.

In embodiments, when the FI robot 126 places the object (e.g., edge ring136) in the load lock 120 b, the FI robot 126 nominally places theobject at a first target location in the load lock using a taughtposition of a robot arm of the FI robot 126. The first target locationmay be at a center of the load lock, or may be at a location that isoffset from the center of the load lock. A first pocket center of afirst blade of the robot arm nominally corresponds to the first targetlocation for the first taught position in embodiments. In embodiments,when the transfer chamber robot 112 picks up the object from the loadlock 120 b, the transfer chamber robot 126 uses a second taught positionof a robot arm of the transfer chamber robot 126. A second pocket centerof a blade of the transfer chamber robot arm nominally corresponds tothe first target location for the second taught position.

In some instances, there is a misalignment or offset between the firsttaught position of the FI robot arm and the second taught position ofthe transfer chamber robot arm. A characteristic error value thatrepresents the misalignment between the first taught position of thefirst robot arm and the second taught position of the second robot armmay be used to correct for the misalignment. For example, the FI robot126 may place the object using the first taught position as modified bythe characteristic error value. When the transfer chamber robot 112picks up the object using the second taught position, the object will bepositioned properly at a center of a pocket in the blade of the transferchamber robot arm. Alternatively, the FI robot 126 may place the objectusing the first taught position, which may cause the object to be placedin the load lock 120 b at a location that is offset from the targetlocation in the load lock. The transfer chamber robot 112 may then usethe second taught position as modified by the characteristic error valueto pick up the object from the load lock. The object will then bepositioned properly at a center of a pocket in the blade of the transferchamber robot arm. Calibration of the FI robot 126 to transfer chamberrobot 112 taught positions for transfer of objects through a load lockis discussed in greater detail below with reference to FIGS. 11-13.

While not shown for clarity in FIG. 1, transfer of edge ring 136 mayoccur while edge ring 136 is positioned on a carrier or adapter, and theend effectors (i.e. blades) of the robots may pick up and place thecarrier or adapter that holds edge ring 136. This may enable an endeffector that is configured for handling of wafers to be used to alsohandle edge ring 136.

FIG. 2A illustrates an example first orientation and position 216 of anedge ring 210 at a processing chamber, according to aspects of thepresent disclosure. The processing chamber may correspond to at leastone of processing chamber 114 a, 114 b, 116 a, 116 b, or 118 a, 118 b ofelectronics processing system 100 illustrated in FIG. 1. In someembodiments, the processing chamber may include a substrate supportassembly 212 configured to support a substrate during a substrateprocess. Edge ring 210 may be configured for placement around thesubstrate support assembly 212. As discussed previously, edge ring 210may be placed by a transfer chamber robot (not shown) at a firstorientation and position 216 at substrate support assembly 212. In someembodiments, first orientation and position 216 may include anorientation error 220. Orientation error 220 may indicate a differencebetween an actual orientation and a target orientation of the edge ring(e.g., between an angle of a flat 222 of edge ring 210 relative to anangle of a flat 224 of the substrate support assembly 212). Inembodiments, flat 222 is configured to mate with flat 224. Theorientation error 220 may be caused by at least a first characteristicerror value associated with the processing chamber. The firstcharacteristic error may result from a variety of sources (e.g., errorin robot angle and/or positioning, the processing chamber not beinginstalled properly during construction of the processing system, etc.).Orientation error 220 may be determined based on an angle formed betweena target orientation and an actual orientation. In one embodiment, theorientation error represents an angle between flat 222 and flat 224.

FIG. 2B illustrates an example second orientation and position 225 ofthe edge ring 210 at the processing chamber, according to aspects of thepresent disclosure. In some embodiments, second orientation 225 mayinclude a positional error (also referred to as a translational error).The positional error may include a first positional error 228 along anx-axis and/or a second positional error 230 along a y-axis. Thepositional error may indicate a difference between an actual positionand a target position of the edge ring. The first positional error 228may be caused by a second characteristic error value in the y-directionand the second positional error 230 may be associated with a thirdcharacteristic error value in the x-direction. The characteristic errorsmay result from a variety of sources (e.g., error in robot angle and/orpositioning, the processing chamber not being installed properly duringconstruction of the processing system, etc.).

FIG. 2C illustrates an example third orientation and position 218 of theedge ring 210 at the processing chamber, according to aspects of thepresent disclosure. The third orientation and position 218 may be acorrect orientation and position for placement of the edge ring aroundthe substrate support. In some embodiments, third orientation andposition 218 in the processing chamber may not include orientation error220 (i.e., there is no difference between the angle of flat 222 and theangle of flat 224), first positional error 228 or second positionalerror 230.

In some embodiments, a processing chamber may be associated with thefirst characteristic error value, the second characteristic error valueand/or the third characteristic error value.

In some embodiments, a transfer recipe may include a combination ofcharacteristic error values, which may be summed to determine a totalcharacteristic error associated with placing an edge ring in aprocessing chamber. The characteristic error values may include, forexample, a first characteristic error associated with a processingchamber and a second characteristic error associated with at leastanother station of the electronics processing system (i.e., load lock120, load port 124, etc.).

FIGS. 3A and 3B illustrate an example initial target orientation 314 andan example corrected target orientation 316 of an edge ring 312 at analigner station 310 of an electronics processing system, according toaspects of the present disclosure. As discussed previously, edge ring312 may ordinarily be aligned by aligner station to an initial targetorientation 314. The edge ring 312 may initially have some angular errorthat may occur during placement of the edge ring in a container (e.g.,FOUP), transport of the container, and/or attachment of the container tothe factory interface. The aligner station may remove such error byaligning the edge ring 312 to the initial target orientation 314. Theinitial target orientation 314 in an example may include a flat of theedge ring 312 aligned perpendicular to a longitudinal axis of an endeffector that picks up the edge ring 312 from the aligner station.

As discussed above, some characteristic error (e.g., angular error) maybe introduced to the edge ring 312 by moving the edge ring from thealigner station to a destination processing chamber. Accordingly, thealigner station may intentionally introduce an inverse of thecharacteristic error into the orientation of the edge ring 312 duringthe alignment process. The initial target orientation as adjusted by thecharacteristic error may correspond to a corrected target orientation316. Accordingly, by introducing the opposite of the characteristicerror to the edge ring during alignment, that finally placed edge ringin the processing chamber will have no characteristic error because theintentionally introduced error will cancel out the characteristic error.In some embodiments, aligner 310 may rotate edge ring 312 along ayaw-axis 318 to position edge ring 312 at the corrected targetorientation 316. In some embodiments, aligner 310 may position edge ring312 at corrected target orientation 316 based on an alignment recipestored at a controller, such as system controller 132 described withrespect to FIG. 1.

As discussed above, stored characteristic errors are used duringalignment of edge rings to intentionally introduce orientation error tothe edge rings. Each processing chamber may have its own characteristicerror, which may be different from the characteristic errors of otherprocessing chambers. Additionally, each load lock may have its owncharacteristic error. Accordingly, an edge ring moved to a firstprocessing chamber through a first load lock may have a differentcombined characteristic error than an edge ring moved to the firstprocessing chamber through a second load lock. In order to determine thecharacteristic error values associated with each processing chamber(and/or each load lock or other station), a calibration procedure may beperformed. The calibration procedure can be used to determine one ormore characteristic error values associated with a transfer sequencebetween a source station and a destination station of the electronicsprocessing system. Accordingly, the calibration procedure accounts forany errors caused by one or more stations and/or robots involved in thetransfer sequence.

Though embodiments are described with reference to transferring objectsbetween an aligner station and a processing chamber, the samecalibration technique may be applied for calibration of a transfersequence between any source and any destination in an electronicsprocessing system. For example, calibration may be performed todetermine any characteristic error associated with transferring anobject from a first robot arm (of an FI robot or a transfer chamberrobot), through a load lock, to a second robot arm (of the FI robot orthe transfer chamber robot). In another example, calibration may beperformed to determine any characteristic error associated withtransferring an object from a FOUP, SSP or load port to a load lock byan FI robot, or vice versa.

FIG. 4 illustrates a calibration of a transfer sequence for transferringan object (e.g., an edge ring, wafer or substrate) between a sourcestation and a destination station, according to aspects of the presentdisclosure. An example is described for calibrating a transfer sequencebetween aligner station 128 and a processing chamber 116 a, 116 b via aload lock 120 b. However, the same process may be used to calibrate atransfer sequence between any source and destination. Operationsassociated with FIG. 4 may be performed, for example, by processinglogic of a controller.

A calibration object 410 may be placed at a target orientation and/orposition at a processing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118b of electronics processing system 100. A target orientation in theprocessing chamber may be an orientation of an object (i.e., calibrationobject 410, substrate 102, etc.) at processing chamber 114 a, 114 b, 116a, 116 b, 118 a, 118 b that meets or exceeds a threshold degree ofaccuracy (i.e., includes an orientation error that exceeds a thresholdorientation error). For example, the target orientation may be anorientation of the object that is within a 0.01° of accuracy, within0.1° of accuracy, within 0.001° of accuracy, or within 0.02° ofaccuracy. Similarly, a target position in the processing system may be aposition of an object that meets or exceeds a threshold degree ofaccuracy. The threshold degree of accuracy for the position may be thesame as or different from the threshold degree of accuracy for theorientation. In some embodiments, the target orientation and/or positionin the processing chamber may be the same as target orientation andposition 218 described with respect to FIGS. 2A-2C.

In some embodiments, calibration object 410 may be at least one of acalibration ring, a calibration disc, or a calibration wafer. In someembodiments, calibration object 410 may be a standard edge ring or astandard substrate. A calibration ring may be a specially designed ringthat is configured to fit around a substrate support assembly of theprocessing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b such thatthe calibration ring has a target orientation and/or position at thesubstrate support assembly to within a target degree of accuracy (e.g.,0.01° of accuracy). Similarly, a calibration wafer may be a speciallydesigned wafer that is configured to fit within, on, over, or around thesupport assembly such that the calibration wafer has a targetorientation and/or position at the substrate support assembly to withinthe target degree of accuracy or can determine an orientation and/orposition of the wafer relative to the target orientation to within atarget degree of accuracy.

In some embodiments, the substrate support assembly may include one ormore coupling components (also referred to as registration features),such as lift pins. The registration features/coupling components arekinematic registration features in embodiments. The calibration object410 may include one or more coupling receptacles that are configured toengage with the one or more registration features of the substratesupport assembly. In some embodiments, the one or more couplingreceptacles are kinematic coupling interfaces. In some embodiments,calibration object 410 may be placed at the substrate support assemblyin processing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b bytransfer chamber robot 112. Calibration object 410, when placed at thesubstrate support assembly, may have an orientation error and/or apositional error, such as orientation error 220 and/or positional errors228, 230 described with respect to FIGS. 2A-2B. In response tocalibration object 410 being placed at the substrate support assembly,one or more registration feature of the substrate support assembly mayengage with a corresponding coupling receptacle (e.g., a correspondingkinematic coupling interface). By each registration feature engagingwith a corresponding coupling receptacle, the orientation error and/orpositional error associated with calibration object 410 may be removedand calibration object 410 may be positioned at the target orientationand/or the target position.

Many different designs of calibration object may be used in accordancewith embodiments of the present disclosure. Such calibration objects inembodiments include a body sized to fit through a slit valve of theelectronics processing system and designed to be transported by robotarms of the electronics processing system. For example, the calibrationobject may have a height and a width or diameter that fits through aslit valve. For example, for a 300 mm wafer processing system, slitvalves may have a width of over 300 mm (e.g., 300 mm plus a clearancemargin) and a height of about 10-50 mm. Accordingly, for such a systemthe calibration object may have a diameter of about 300 mm or less and aheight of less than 10 mm to less than 50 mm in an embodiment. For a 450mm wafer processing system, slit valves may have a width of over 450 mmand a height of about 10-50 mm. Accordingly, for such a system thecalibration object may have a diameter of about 450 mm or less and aheight of less than 10 mm to less than 50 mm in an embodiment. Somewafer processing systems may be configured to permit exchange of processkit rings through slit valves. For such wafer processing systems, theslit valves may have a width sufficient to accommodate a 15.25 inchdiameter process kit ring (e.g., may have a width of over 15.25 inches,such as 15.25 inches plus a clearance margin). The body may bedisc-shaped, ring-shaped, or have another shape. The calibration objectmay be directly picked and placed by robot arms, or may be disposed on acarrier or adapter that enables the carrier plus the calibration objectsupported by the carrier to be picked and placed by the robot arms. Thisenables the calibration object to be transferred between stations in theelectronics processing system in an automated fashion without manualintervention by a user.

In some embodiments, the calibration object has a shape that is anegative of a region of a station at which the calibration object isdesigned to be placed for calibration purposes. For example, a bottomsurface of the calibration object may have a shape that is a negative ofan upper surface of a substrate support assembly. The calibration objectin embodiments has enough lead-in to enable it to be placed at aninitially incorrect position and/or orientation, and then automaticallyadjust to a correct position and/or orientation. Accordingly, the bottomsurface of the calibration object may snugly mate with the upper surfaceof the substrate support assembly. This enables the calibration objectto capture a characteristic orientation and/or position of a region inthe station (e.g., of the substrate support of a processing chamber).That characteristic orientation and/or position may then be used forcalibration purposes. While embodiments are discussed with reference todetermining a characteristic position and/or orientation of a substratesupport for placement of an edge ring in a process chamber, thecalibration object may alternatively or additionally be configured todetermine a characteristic position and/or orientation of a chuck, aplunger, a cathode, etc. in a processing chamber. Additionally, oralternatively, the calibration object may be configured to determine acharacteristic position and/or orientation of a substrate support in aload lock, a load port, a FOUP, an SSP, or another station.

In embodiments, the calibration object has a body formed from a solidsintered ceramic (e.g., composed of Al₂O₃, AlN, Y₂O₃, Y₃Al₅O₁₂ (YAG),ZrO₂, or some other ceramic material). Accordingly, the calibrationobject may be usable at temperatures of up to 400 degrees C., up to 600degrees C., or up to 800 degrees C. or more without damage to thecalibration object. This enables the calibration object to be used toperform calibration and determine target positions and/or orientation ofobjects (e.g., substrates or edge rings) in processing chambers atprocess temperatures, which may be different from the target positionsand/or orientations at room temperature. Accordingly, by designing thecalibration objects to be usable at elevated process temperatures, anaccuracy of a calibration performed using the calibration object may beimproved. The calibration object is entirely composed of the solidsintered ceramic material in some embodiments. In other embodiments, thecalibration object includes other components (which may also be heatresistant) that may be composed of different materials. For example, thecalibration object may include slip-resistant buttons or pads disposedon a bottom surface of the calibration object. The slip-resistantbuttons or pads may be composed of rubber, perfluoropolymer, or someother material. The slip-resistant buttons or pads may be positioned atpoints where the bottom surface of the calibration object contacts ablade of a robot arm and/or where the calibration object contacts acarrier or adapter. The slip-resistant buttons or pads prevent movementof the calibration object on a carrier or blade while it is transferredbetween stations.

In embodiments, the calibration object includes one or a plurality ofkinematic coupling interfaces. The kinematic coupling interfaces mayinclude contoured slopes that guide the calibration object to a targetposition and/or orientation when they engage with registration featuresat a station. In some embodiments, the calibration object includes threekinematic coupling interfaces. The kinematic coupling interfaces mayprovide up to a 0.5 mm, 1 mm, 2 mm, 3 mm, 4 mm, 5 mm, 6 mm, 7 mm, 10 mmor greater lead-in in embodiments. The lead-in represents an amount ofinitial orientation error (rotational error) and/or positional errorthat can be accommodated by the kinematic coupling interfaces and thatthe kinematic coupling interfaces can correct for when they engage withregistration features at a station. The registration features may befixed (static) registration features or movable (dynamic) registrationfeatures. An example of a fixed registration feature is a region on anexterior perimeter of a substrate support assembly, where the region hastight machine tolerances. Another example of a fixed registrationfeature is a series of fixed pins (e.g., three pins or wafer centeringcones). In the example of the fixed pins, the kinematic registrationinterfaces may be a set of sloped slots (e.g., three slots) in an outerperimeter of the calibration object that line up with the fixed pins. Insome embodiments, the kinematic coupling interfaces comply with SemiE57-0616.

In embodiments, the calibration object includes a fiducial. The fiducialis disposed at a side of the calibration object, and may be at an outerregion (e.g., at or near a perimeter) of the calibration object orcloser to a center of the calibration object. The fiducial may be anotch, groove, projection, flat, or other feature that is usable todetermine an orientation of the calibration object.

FIG. 5A illustrates an example calibration object 500, according toaspects of the present disclosure. As shown, the calibration object inone embodiment has a disc-shaped body 502. Alternatively, the body ofthe calibration object may have another shape, such as a ring shape. Thedisc-shaped body 502 includes a plurality of kinematic couplinginterfaces 505 a, 505 b, 505 c in the body 502. The plurality ofkinematic coupling interfaces 505 a-c are configured to engage with arespective plurality of registration features (e.g., lift pins) of afirst station of the electronics processing system (e.g., of aprocessing chamber) and to guide the calibration object 500 to a targetposition and a target orientation at the first station. The body 502additionally includes a fiducial 510 disposed at a side of the body(e.g., at a location on an outer perimeter of the body 502). Thefiducial is usable to determine an orientation of the calibration object500. The lift pins may lift to engage with the kinematic couplinginterfaces 505 a-505 c. Such engagement of the kinematic couplinginterfaces 505 a-505 c with the lift pins causes a position and/ororientation of the calibration object 500 to change to a target positionand/or orientation.

FIG. 5B illustrates an example calibration object 520, according toaspects of the present disclosure. As shown, the calibration object 520in one embodiment has a ring-shaped body 522. Alternatively, the body ofthe calibration object may have another shape, such as a disc shape. Thering-shaped body 522 includes a plurality of kinematic couplinginterfaces 525 a, 525 b, 525 c in the body 522. In one embodiment, theplurality of kinematic coupling interfaces 525 a-525 c are legs thatextend from a bottom of the body 522 at positions along a perimeter ofthe body 522. The plurality of kinematic coupling interfaces 525 a-525 care configured to engage with a respective plurality of registrationfeatures of a first station of the electronics processing system (e.g.,of a processing chamber) and to guide the calibration object 500 to atarget position and a target orientation at the first station. One ofthe plurality of registration features may be a flat at a location on anouter perimeter of a substrate support.

In one embodiment, the kinematic coupling interfaces 525 a-525 c eachinclude a curved or chamfered bottom that is configured to mate with alip of the substrate support assembly of the station. In embodiments,the kinematic coupling interfaces 525 a-525 c include three kinematiccoupling interfaces that provide 3-point locking to the outer perimeterof the substrate support assembly. The kinematic coupling interfaces 525a-525 c engage with the registration features as the calibration object520 is lowered onto a substrate support assembly of a station, causing aposition and/or orientation of the calibration object 520 to change to atarget position and/or orientation. Lift pins in the substrate supportassembly may then be used to lift the calibration object 520 from thesubstrate support assembly without disturbing the position and/ororientation of the calibration object 520.

The body 522 of the calibration object additionally includes a fiducial530 disposed at a side of the body (e.g., at a location on an innerregion of the ring-shaped body 522). The fiducial is usable to determinean orientation of the calibration object 520. In embodiments, thecalibration object 520 includes a support structure 531 that includesone or more beams 533 that connect to multiple positions on thering-shaped body 522. The support structure 531 further includes aplanar object 532 (e.g., a disc as illustrated) at or near a center ofthe ring-shaped body 522 and connected to the beam(s) 533. The supportstructure 531 may be configured to interface with a blade of a robot armand/or with a carrier or adapter for a process kit ring.

FIGS. 5C-5D illustrate an example calibration object 540 on a substratesupport 580 of a station, according to aspects of the presentdisclosure. FIG. 5C illustrates the full calibration object 540, whileFIG. 5D shows half of the calibration object 540, where the calibrationobject 540 was cut along a line running through a center of thecalibration object 540 in FIG. 5D. Calibration object 540 includes adisc-shaped ceramic body 542. The ceramic body 542 includes a left-sidecutout 554 a in a left side of the body and a right-side cutout 554 b ina right side of the body 542. The left-side cutout 554 a and theright-side cutout 554 b are mirror images of one another (i.e., they arelinearly symmetrical about a line running through the center of the body542). In one embodiment, the left-side cutout 554 a and the right-sidecutout 554 b are usable to detect an orientation of the calibrationobject based on a difference between a first position of a robot armholding the calibration object at which the left-side cut-out isdetected by a local center finder and a second position of the robot armholding the calibration object at which the right-side cutout isdetected by the local center finder.

In an embodiment, the calibration object 540 includes a plurality ofarc-shaped cutouts 555 in the body that are offset from an outerperimeter of the body. The arc-shaped cutouts 555 may include theleft-side cutout 554 a and right-side cutout 554 b. A first machinetolerance of at least one side of each of the arch-shaped cutouts isgreater than a second machine tolerance of the outer perimeter of thebody 542 in an embodiment. For example, the side of the arc-shapedcutouts that is nearest the perimeter of the body 542 may have tightmachine tolerances, and may be used by an aligner station to determinerunout and/or orientation of the calibration object 540 rather than theouter perimeter of the calibration object 540. Alternatively, the outerperimeter of the calibration object 540 may have tight machinetolerances and may be usable by the aligner station to determineorientation and/or runout of the calibration object.

In an embodiment, the body 542 includes a first plurality of kinematiccoupling interfaces 560 and a second plurality of kinematic couplinginterfaces 562 in the body 542. The first plurality of kinematiccoupling interfaces 560 are configured to engage with a respective firstplurality of registration features of a station of the electronicsprocessing system and to guide the calibration object to an intermediateposition and/or an intermediate orientation at the station. The secondplurality of kinematic coupling interfaces are configured to engage witha respective second plurality of registration features of the station.As illustrated, the first plurality of kinematic coupling interfaces 560are a plurality of recesses in a bottom surface of the body 542, and thesecond plurality of kinematic coupling interfaces 562 comprise aplurality of regions proximate to an outer perimeter of the body. Inparticular, the second plurality of kinematic coupling interfaces 562are regions of the side of the arc-shaped cutouts 555 that is nearestthe perimeter of the body 542. The first plurality of kinematic couplinginterfaces have a first lead-in, and the second plurality of kinematiccoupling interfaces have a second lead-in that is smaller than the firstlead-in. The first plurality of kinematic coupling interfaces areconfigured to engage with a first plurality of kinematic registrationfeatures to guide the second plurality of kinematic coupling interfacesonto the second plurality of kinematic registration features (andpartially correct an orientation error and/or positional error). Thecoupling of the second plurality of kinematic coupling interfaces withthe second plurality of registration features then guides thecalibration object to a final target orientation and/or target position.

FIGS. 5E-5F illustrate placement of example calibration object 540 ontoa substrate support 580 (e.g., a cathode of a substrate support) at astation, according to aspects of the present disclosure. In FIG. 5E,wafer lift pins 582 are extended, and engage with the first plurality ofkinematic coupling interfaces 560 of calibration object 540, partiallycorrecting an orientation and/or position of the calibration object 540.In FIG. 5F, the wafer lift pins 582 are lowered, and the secondplurality of kinematic coupling interfaces 562 engage with an outerperimeter of a lip of the substrate support 580, completing correctionof the orientation and/or position of the calibration object at thestation. The two sets of kinematic coupling interfaces and correspondingregistration features are used to increase an amount of correction inorientation error and/or positional error that can be achieved by thecalibration object. The kinematic coupling interfaces 560 may correctfor gross errors, and the kinematic coupling interfaces 562 may correctfor fine errors in an embodiment.

FIG. 5G illustrates removal of the example calibration object 540 fromthe station of FIGS. 5A-5B, according to aspects of the presentdisclosure. A separate set of lift pins (e.g., edge ring lift pins 584)are used to lift the calibration object 540 off of the cathode 580without disturbing the orientation or x-y position of the calibrationobject so that it can be retrieved by a blade of a robot arm.

Returning to FIG. 4, after the calibration object 410 is placed at thetarget orientation and/or target position at a processing chamber 114 a,114 b, 116 a, 116 b, 118 a, 118 b, calibration object 410 may beretrieved, by transfer chamber robot 112, from processing chamber 114 a,114 b, 116 a, 116 b, 118 a, 118 b and placed in a load lock 120connected to transfer chamber 110. Factory interface robot 126 mayretrieve calibration object 410 from load lock 120 and place calibrationobject 410 at aligner station 128. Calibration object 410 may be placedat aligner station 128 at a first orientation and/or a first position.The first orientation may include a first characteristic errorassociated with the processing chamber. Optionally, the first positionmay include one or more additional characteristic errors (e.g., anx-position characteristic error and/or a y-position characteristicerror). For example, the first orientation may include an inverse of acharacteristic error that would be introduced with an edge ring that wasaligned to an initial target orientation at the aligner station 128 andthen moved to the processing chamber.

In response to calibration object 410 being placed at aligner station128, the first orientation of the calibration object 410 at the alignerstation 128 may be determined. Additionally, in some implementations adifference between the first orientation and an initial targetorientation at the aligner station is determined. The initial targetorientation at the aligner may be an orientation of an object (i.e.,calibration object 410, substrate 102) where, in response to the objectbeing transferred from aligner station 128 to a processing chamber 114a, 114 b, 116 a, 116 b, 118 a, 118 b, the object should nominally beplaced at a target orientation upon receipt at processing chamber 114 a,114 b, 116 a, 116 b, 118 a, 118 b. However, the characteristic errorcauses the objects that are oriented to the initial target orientationat the aligner station to not have the target orientation at theprocessing chamber, and to instead have a characteristic error.

The first orientation and/or the difference between the firstorientation and the initial target orientation may indicate a firstcharacteristic error value associated with processing chamber 114 a, 114b, 116 a, 116 b, 118 a, 118 b (or an inverse of the characteristic errorvalue associated with the processing chamber 114 a, 114 b, 116 a, 116 b,118 a, 118 b). The characteristic error value may be associated with aparticular transfer sequence between a source station (e.g., the alignerstation) and a destination station (e.g., a processing chamber). Thecharacteristic error value may quantify a characteristic orientationerror associated with moving objects from the source station to thedestination station (e.g., to processing chamber 114 a, 114 b, 116 a,116 b, 118 a, 118 b). The characteristic error value may be recorded ina storage medium (i.e., a data storage device of system controller 132).In some embodiments, the characteristic error value may be retrievedfrom the storage medium and used by system controller 132 for alignmentof objects to be placed at a destination station (e.g., processingchamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b) associated with thecharacteristic error value, as discussed above.

As discussed above, one common destination station is at a processingchamber. However, embodiments are not limited to processing chambers asdestination stations. In addition to determining the characteristicerror value associated with a processing chamber 114 a, 114 b, 116 a,116 b, 118 a, 118 b, a characteristic error associated with one or moreother stations (i.e., load lock 120, load port 124, etc.) of theelectronics processing system may be determined. For example,calibration object 410 may aligned to a target orientation in a loadlock, retrieved, by factory interface robot 126, placed at a secondorientation at aligner station 128. The calibration object may include aplurality of kinematic coupling interfaces having shapes and locationson the body of the calibration object to interface with registrationfeatures in the load lock. For example, load locks often include waferlift pins. The calibration object in embodiments includes kinematiccoupling interfaces to engage with wafer lift pins in load locks of theelectronics processing system.

The second orientation may be determined. Additionally, a differencebetween the second orientation and an initial target orientation may bedetermined. The second orientation and/or the difference may indicate anorientation error caused by a first characteristic error value of loadlock 120. The characteristic error value associated with the load lockmay be recorded in the storage medium. In some embodiments, thecharacteristic error value previously described and the characteristicerror value of the load lock may be retrieved from the storage mediumand used by system controller 132 for alignment of objects placed atload lock 120 and subsequently placed at processing chamber 114 a, 114b, 116 a, 116 b, 118 a, 118 b. The same (and/or a similar) process maybe performed in order to determine a characteristic error valueassociated with load port 124, an SSP and/or a cassette (e.g., a FOUP).In some embodiments, a single load lock is used for transfer of edgerings to processing chambers. Accordingly, in such embodiments thecharacteristic error value associated with a processing chamber may alsoinclude in it any characteristic error value caused by the single loadlock.

In some embodiments, a single calibration object is configured forcalibration of multiple different types of stations (e.g., forcalibration of wafer transfer sequences to particular types ofdestination stations). For example, a single calibration object may beconfigured for calibration of both load locks and processing chambers.The calibration object may include first kinematic coupling interfacesfor engaging with registration features of load locks and secondkinematic coupling interfaces for engaging with registration features ofprocessing chambers. In one embodiment, a calibration object may bealigned to a first orientation for placement into a first type ofdestination station (e.g., a load lock) and may be aligned to a secondorientation for placement into a second type of destination station(e.g., a processing chamber). In some embodiments, different calibrationobjects are used for calibration of different types of stations (e.g.,for calibration of wafer transfer sequences to different types ofdestination stations).

After calibrating a wafer transfer sequence between a source station anda destination station, an object (e.g., an edge ring) aligned at alignerstation 128 may initially have a corrected target alignment at thesource station, may be transferred to a destination station (e.g.,processing chamber 114 a, 114 b, 116 a, 116 b, 118 a, 118 b), and mayhave a target orientation at the processing chamber to a high degree ofaccuracy. In some embodiments, the object may be a process kit ring. Theprocess kit ring may be retrieved by factory interface robot 126 from astorage location, such as a substrate carrier 122 (e.g., FOUP) or SSP.The process kit ring may be placed by factory interface robot 126 ataligner station 128. In some embodiments, it may be determined that theprocess kit ring is to be placed at a particular processing chamber 114a, 114 b, 116 a, 116 b, 118 a, 118 b (e.g., according to a particulartransfer sequence or recipe). For example, it may be determined that theprocess kit ring is to be placed at processing chamber 116 b. Inadditional embodiments, it may be determined that the process kit ring,prior to being placed at processing chamber 116 b, is to be placed at aparticular load lock 120 b. In response to determining that process kitring is to be placed at processing chamber 116 b and optionally aparticular load lock 120 b, a first characteristic error valueassociated with processing chamber 116 b and/or a second characteristicerror value associated with load lock 120 b may be retrieved from thestorage medium. The process kit ring may be aligned, using at least thefirst characteristic error value (and optionally the secondcharacteristic error value), to a corrected target orientation.Additionally, further characteristic error value(s) associated with theprocessing chamber and/or load lock may also be used (e.g.,characteristic error values associated with correction of positionalerrors). The corrected target orientation may be based on the initialtarget orientation as adjusted by at least the first characteristicerror value and/or the second characteristic error value. Additionally,or alternatively, a corrected target position may be based on theinitial target position as adjusted by at least one or more additionalcharacteristic error values associated with positional errors. Inresponse to the process kit ring being aligned to the corrected targetorientation and/or target position, the process kit ring may beretrieved from aligner station 128 and placed at load lock 120 b byfactory interface robot 126. In some embodiments, to correct fororientation errors the edge ring is orientated to the adjusted initialtarget position by the aligner station, and to correct for positionalerrors the robot is picked up by the FI robot such that it is off centerrelative to a pocket center of a blade of the FI robot. The process kitring may then be retrieved from load lock 120 b and placed at processingchamber 116 b by transfer chamber robot 112. In some embodiments, theprocess kit ring may be placed at processing chamber 116 b at a targetorientation within a degree of accuracy between approximately 0.2° and0.0000001° and/or a target position to within a degree of accuracybetween approximately 0.1° and 0.01°. In some embodiments, the processkit ring may be placed at processing chamber 116 b at a targetorientation within a degree of accuracy between approximately 0.001° and0.00001°.

In some embodiments, one or more distinct characteristic error value maybe determined for each processing chamber 114 a, 114 b, 116 a, 116 b,118 a, 118 b, in accordance with embodiments described above. Forexample, the first characteristic error value may be associated withprocessing chamber 116 b, a second characteristic error value may beassociated with processing chamber 116 a, a third characteristic errorvalue may be associated with processing chamber 114 a, and so on.

FIG. 4 has been described with reference to calibrating a transfersequence between a source station and a destination station. Inparticular, embodiments have been described with reference tocalibrating the transfer sequence to accommodate a unique targetposition and/or orientation associated with the destination station. Inother embodiments, a transfer sequence between the FI robot 126 and thetransfer chamber robot 112 via a load lock (e.g., load lock 120 a) maybe calibrated. Such a calibration may be performed by placing, by afirst robot arm of the transfer chamber robot 112 or the FI robot 126, acalibration object 412 into a load lock 120 a that separates the factoryinterface 106 from the transfer chamber 110. The calibration object isplaced into the load lock such that a calibration object center is at afirst target location associated with a first taught position of thefirst robot arm. A first pocket center of a first blade of the firstrobot arm nominally corresponds to the first target location for thefirst taught position. A second robot arm of the FI robot 126 or thetransfer chamber robot 112 retrieves the calibration object from theload lock 120 a onto a second blade of the second robot arm using asecond taught position of the second robot arm. A second pocket centerof the second blade nominally corresponds to the first target locationfor the second taught position. However, the calibration object centermay be offset from the second pocket center by a first offset amountafter retrieving the calibration object.

In one embodiment, the first robot arm is a robot arm of the FI robot126 and the second robot arm is a robot arm of the transfer chamberrobot 112. In another embodiment, the first robot arm is a robot arm ofthe transfer chamber robot 112 and the second robot arm is a robot armof the FI robot 126.

A sensor that is in or connected to a) the factory interface if thesecond robot arm is on the FI robot orb) the transfer chamber if thesecond robot arm is on the transfer chamber robot 112 is used todetermine the first offset amount between the calibration object centerand the second pocket center. If the second robot arm is on the FI robot126, then the FI robot 126 places the calibration object 412 at thealigner station 128. The aligner station 128 can then determine a runoutof the calibration object positioned on a substrate support of thealigner station, and from the runout can determine the offset. Theoffset may include a first offset in a y-direction and/or a secondoffset in an x-direction. In some embodiments, additional LCFs (notshown) are placed at the interfaces between the load locks 120 a, 120 band the FI 106. In such embodiments, these LCFs may be used to determinethe offset without use of the aligner station 128. If the second robotarm is on the transfer chamber robot 112, then the LCF 152 associatedwith the load lock 120 a is used to determine the offset. The systemcontroller 132 then determines a first characteristic error value thatrepresents a misalignment between the first taught position of the firstrobot arm and the second taught position of the second robot arm basedon the first offset amount. The first characteristic error value mayinclude a pair of characteristic error vales, where one characteristicerror value is associated with offset in the x-direction and anothercharacteristic error value is associated with offset in the y-direction.System controller 132 then records the first characteristic error valuein a storage medium. One of the first robot arm or the second robot armthen uses the first characteristic error value to compensate for themisalignment for objects (e.g., substrates, edge rings, etc.)transferred between the first robot arm and the second robot arm via theload lock 120 a. For example, the FI robot 126 may adjust the firsttaught position by a negative of the characteristic error value whenplacing an object into load lock 120 a. The transfer chamber robot 112may then pick up the object using the second taught position, withoutmodification. Alternatively, the FI robot may place the object in theload lock 120 a using the first taught position. The transfer chamberrobot 112 may then use the second taught position as modified by thecharacteristic error value to pick up the object from the load lock 120a. In either case, the picked up object does not have the characteristicerror on the blade of the transfer chamber robot arm.

FIGS. 6-13 are flow diagrams of various embodiments of methods 600-1300for calibrating components and/or a transfer sequence of an electronicsprocessing system and/or for transferring objects between components ofthe electronics processing system using characteristic error valuesdetermined from calibration. The methods are performed by processinglogic that may include hardware (circuitry, dedicated logic, etc.),software (such as is run on a general purpose computer system or adedicated machine), firmware, or some combination thereof. Someoperations of methods 600-1300 may be performed by or initiated by acomputing device, such as system controller 132 of FIG. 1.

For simplicity of explanation, the methods are depicted and described asa series of acts. However, acts in accordance with this disclosure canoccur in various orders and/or concurrently, and with other acts notpresented and described herein. Furthermore, not all illustrated actsmay be performed to implement the methods in accordance with thedisclosed subject matter. In addition, those skilled in the art willunderstand and appreciate that the methods could alternatively berepresented as a series of interrelated states via a state diagram orevents.

FIG. 6 is a flow chart of a method 600 for calibrating a transfersequence between a source station and a destination station of anelectronics processing system, according to embodiments of the presentdisclosure. At block 610, a calibration object is retrieved, by a firstrobot arm of a transfer chamber, from a first station (e.g., aprocessing chamber) connected to the transfer chamber. The calibrationobject may have been placed in the processing chamber by the robot arm,and may have a target orientation and/or position in the processingchamber. In some embodiments, the calibration object may be at least oneof a calibration ring, a calibration wafer, or a calibration disc. Atblock 620, the calibration object is placed, by the first robot arm, ina load lock connected to the transfer chamber. At block 630, thecalibration object is retrieved from the load lock by a second robot armof a factory interface connected to the load lock.

At block 640, the calibration object is placed, by the second robot arm,at a first orientation and/or position at an aligner station housed inor connected to the factory interface. At block 650, the firstorientation at the aligner station is determined. Additionally, adifference between the first orientation at the aligner station and aninitial target orientation at the aligner station is determined. Adifference between a first position and an initial target position mayalso be determined. At block 660, one or more characteristic errorvalues associated with the processing chamber are determined. At block670, the one or more characteristic error values are recorded in astorage medium. In response to an object being received at the alignerstation to be placed at the processing chamber, the characteristic errorvalue(s) may be received from the storage medium. The aligner stationand/or FI robot may move the object to be positioned at the targetorientation based on the characteristic error value(s).

FIG. 7A is a flow chart of a method 700 for placing an object such as aprocess kit ring at a target orientation and/or a target position at adestination station based on one or more determined characteristic errorvalues associated with a transfer sequence between a source station andthe destination station, according to embodiments of the presentdisclosure. Method 700 may be performed after the calibration method 600is performed. At block 710, a system controller causes the second robotarm (as introduced in FIG. 6) to retrieve an object (e.g., an edge ring,a cover wafer, a substrate, etc.) from a second station. The secondstation may be an SSP or a cassette such as a FOUP. At block 715, thesystem controller causes the second robot arm to place the object at thealigner station. At block 720, the system controller determines that theobject is to be placed at the first station (e.g., the processingchamber).

At block 725, the system controller causes the aligner station to alignthe object using the first characteristic error value and optionallyusing one or more additional characteristic error values. The alignerstation may align the object to a corrected target orientation that isbased on the initial target orientation as adjusted by the firstcharacteristic error value and/or to a corrected target position that isbased on the initial target position as adjusted by the one or more oneor more additional characteristic error values. At block 730, the systemcontroller causes the second robot arm to retrieve the object from thealigner station. In some embodiments, the one or more additionalcharacteristic error values are used to adjust a positioning of theblade of the second robot arm during retrieval of the aligned object.For example, in embodiments the aligner station may not be able toadjust an x or y position of the object. However, the second robot armmay pick up the object such that the object is off center from a pocketof the blade of the second robot arm. The one or more additionalcharacteristic error values may be used to determine how far off centerto cause the object to be in the x and/or y directions.

At block 735, the system controller causes the second robot arm to placethe object in the load lock that was used during calibration. At block740, the system controller causes the first robot arm (as introduced inFIG. 6) to retrieve the object from the load lock. At block 745, thesystem controller causes the first robot arm to place the object in thefirst station (e.g., the processing chamber). The object placed in thefirst station has (or approximately has) the target orientation and/orthe target position in the first station.

FIG. 7B depicts a method 748 for placing an object such as a process kitring at a target orientation at a processing chamber based on adetermined characteristic error value associated with the processingchamber, according to embodiments of the present disclosure. At block750, a controller operatively coupled to a first robot arm, a secondrobot arm, and an aligner station may cause the second robot arm to pickup a first process kit ring from a storage location and place the firstprocess kit ring at the aligner station. At block 755, it may bedetermined that the first process kit ring is to be placed in a firstprocessing chamber of a plurality of processing chambers.

At block 760, the controller causes the first process kit to be aligned,at the aligner station, using a first characteristic error value. Thefirst characteristic error value may be associated with the firstprocessing chamber, in accordance with previously described embodiments.The aligner station may align the first process kit ring to a correctedtarget orientation that is based on the initial target orientation asadjusted by the first characteristic error value.

At block 765, the controller causes the second robot arm to pick up thefirst process kit ring from the aligner station and place the firstprocess kit ring in the load lock. At block 770, the controller causesthe first robot arm to pick up the first process kit ring from the loadlock and place the first process kit ring in the first processingchamber. The first process kit ring may be placed in the firstprocessing chamber at (or approximately at) a target orientation in thefirst processing chamber. For example, the process kit ring may beplaced at the target orientation plus or minus an error of as little as0.2° to as little as 0.01°.

FIG. 8 is a flow chart for a method 800 of calibrating a transfersequence between a source station and a destination station of anelectronics processing system, according to embodiments of the presentdisclosure. Method 800 is similar to method 600, except that in method800 the source station and the destination station may both be attachedto or accessible from the FI or the transfer chamber, or one station maybe attached to and/or accessible from the FI and the other station maybe attached to and/or accessible from the transfer chamber. At block 810of method 800, a system controller causes a first robot arm to place acalibration object at a target orientation and/or at a target positionin a first station. The calibration object may be any of theaforementioned calibration objects. The act of placing the calibrationobject onto the first station may cause it to become aligned andpositioned at the target orientation and/or the target position. Atblock 820, the system controller causes the first robot arm to retrievethe calibration object from the first station without disturbing theorientation and/or position that was achieved during placement of thecalibration object at the first station.

At block 830, the system controller causes the calibration object to betransferred to an aligner station. If the first station was at orconnected to the FI, then the first robot arm places the calibrationobject in the aligner station, which is connected to or in the FI. Ifthe first station was at or connected to the transfer chamber, then thefirst robot arm places the calibration object in a load lock, a secondrobot arm in the FI retrieves the calibration object from the load lock,and the second robot arm places the calibration object in the alignerstation.

At block 840, the system controller uses the aligner station todetermine the first orientation at the aligner station. Additionally,the system controller may use the aligner station to determine adifference between the first orientation at the aligner station and aninitial target orientation at the aligner station. The initial targetorientation at the aligner station is associated with the targetorientation in the first station. Additionally, or alternatively, thesystem controller determines a difference between the first position atthe aligner station and an initial target position at the alignerstation. The initial target position at the aligner station isassociated with the target position in the first station.

At block 850, the system controller determines a first characteristicerror value associated with the first station based on the firstorientation. In some embodiments, the first characteristic error valueis determined based on the difference between the first orientation andthe initial target orientation. Additionally or alternatively, thesystem controller determines one or more additional characteristic errorvalues (e.g., a characteristic error value in the x-direction and acharacteristic error value in the y-direction) associated with the firststation based on a difference between the first position and the initialtarget position. At block 860, the system controller records the firstcharacteristic error value and/or the one or more additionalcharacteristic error values in a storage medium.

FIG. 9 is a flow chart of a method 900 for placing an object at a targetorientation and/or a target position at a destination station based onone or more determined characteristic error values associated with atransfer sequence between a source station and the destination station,according to embodiments of the present disclosure. Method 900 may beperformed after the calibration method 800 is performed. At block 910, asystem controller causes the first robot arm (as introduced in FIG. 8)to retrieve an object (e.g., an edge ring, a cover wafer, a substrate,etc.) from a second station. The second station may be a cassette suchas a FOUP. At block 920, the system controller causes the first robotarm to place the object at the aligner station. At block 925, the systemcontroller determines that the object is to be placed at the firststation (e.g., the processing chamber). The first station (introduced inFIG. 8) may be a FOUP, SSP, load lock, or other station in or attachedto an FI.

At block 930, the system controller causes the aligner station to alignthe object using the first characteristic error value and optionallyusing one or more additional characteristic error values. The alignerstation may align the object to a corrected target orientation that isbased on the initial target orientation as adjusted by the firstcharacteristic error value and/or to a corrected target position that isbased on the initial target position as adjusted by the one or moreadditional characteristic error values. At block 940, the systemcontroller causes the second robot arm to retrieve the object from thealigner station. In some embodiments, the one or more additionalcharacteristic error values are used to adjust a positioning of theblade of the second robot arm during retrieval of the aligned object.For example, in embodiments the aligner station may not be able toadjust an x or y position of the object. However, the second robot armmay pick up the object such that the object is off center from a pocketof the blade of the second robot arm. The one or more additionalcharacteristic error values may be used to determine how far off centerto cause the object to be in the x and/or y directions.

At block 950, the system controller causes the first robot arm to placethe object in the first station. The object placed in the first stationhas (or approximately has) the target orientation and/or the targetposition in the first station.

FIG. 10 is flow chart for a method 1000 of determining an accuracy of atransfer sequence between an aligner station and a second station of anelectronics processing system, according to embodiments of the presentdisclosure. Method 1000 may include at block 1010 repeating theoperations of method 600 or of method 800 a plurality of times. Eachiteration of performing method 600 or method 800 may provide slightlydifferent results. For example, the first characteristic error valueand/or one or more additional characteristic error values may beslightly different with each iteration. These differences in thecharacteristic error values from run to run may indicate a repeatabilityand/or accuracy of the transfer sequence that was calibrated. At block1020, the system controller determines a standard deviation of thecomputed characteristic error values. For example, a standard deviationfor the first characteristic error value (associated with orientation oryaw error) may be computed, a standard deviation for a secondcharacteristic error value (associated with x-position error) may becomputed and/or a standard deviation for a third characteristic errorvalue (associated with z-position error) may be computed. At block 1025,an accuracy or repeatability of the transfer sequence may be determinedbased on the standard deviation(s).

FIG. 11 is flow chart for a method 1100 of determining whether atransfer sequence is out of calibration, according to embodiments of thepresent disclosure. A transfer sequence may be calibrated, and theactual position and/or orientation that is achieved for the transfersequence may slowly drift over time after such calibration. This may bedue to wear on one or more robots, for example. Additionally, oralternatively, a sudden shift may occur if, for example, a processingchamber is jarred or maintenance is performed on a processing chamber orrobot. To detect such drift and/or sudden changes, calibrationoperations may be performed periodically.

At block 1110 of method 1100, the operations of method 600 or method 800are performed multiple times. The operations of method 600 or method 800may initially be performed to calibrate a transfer sequence.Subsequently, the operations of method 600 or method 800 may again beperformed one or more times to verify that a previously performedcalibration is still accurate.

At block 1115, the system controller compares the characteristic errorvalues between the two or more times that the calibration procedure wasperformed. The system controller determines whether there are anydifferences between the different computations of the characteristicerror values. For example, the system controller may determine whetherthere is a difference between the originally computed characteristicerror value(s) and newly computed characteristic error value(s). If thecalibration process has been performed more than twice, then multiplecomparisons may be made. The system controller may determine, based onsuch comparisons, any drift in the computed characteristic error valuesor any sudden change in the characteristic error values. If a differenceis determined and that difference exceeds a difference threshold, thenthe method proceeds to block 1120 and system controller determines thatthe system has changed (e.g., due to drift or a sudden change) and thatthe original result transfer sequence is out of calibration. The newresult of the latest run of the calibration procedure may be used tooverwrite the original characteristic error values. If there is nodifference or a determined difference between the characteristic errorvalues is below a threshold, then the method continues to block 1125 andthe system controller determines that the transfer sequence is still incalibration.

FIG. 12 is flow chart for a method 1200 of calibrating taught positionsof two robot arms that transfer objects to one another via a load lock,according to embodiments of the present disclosure. At block 1210 ofmethod 1200, a system controller causes a first robot arm in one of afactory interface or a transfer chamber to place a calibration objectinto a load lock. The calibration object may be a standard substrate ormay be any other calibration object discussed herein. At block 1220, thesystem controller causes a second robot arm in a second one of thefactory interface or the transfer chamber to retrieve the calibrationobject from the load lock. At block 1225, the system controller uses asensor (e.g., an LCF or an aligner station) to determine a first offsetamount between a first taught position of the first robot arm and asecond taught position of the second robot arm. These two taughtpositions should line up, but often there is misalignment between thetwo. At block 1230, the system error determines a first characteristicerror value that represents a misalignment between the first taughtposition of the first robot arm and the second taught position of thesecond robot arm based on the first offset amount. At block 1235, thesystem controller records the first characteristic error value in astorage medium.

The first characteristic error value may be used to correct for much ofthe misalignment between the first and taught positions. However, robotarms frequently overshoot or undershoot taught positions, which can becorrected by further refinement of corrections to the taught positions(e.g., determining finer or smaller additional characteristic errorvalues). Accordingly, in one embodiment at block 1240 the systemcontroller again causes the first robot arm to place the calibrationobject into the load lock. This time, the system controller causes thefirst robot arm to use the first taught position, optionally as modifiedby the first characteristic error value, to place the calibration objectin the load lock. At block 1245, the system controller causes the secondrobot arm to use the second taught position, optionally as modified bythe first characteristic error value, to retrieve the calibration objectfrom the load lock. The first characteristic error value is used toadjust either the first taught position or the second taught position tocorrect for the determined offset.

At block 1250, the system controller uses the sensor (e.g., LCF oraligner station) to determine a new offset amount. The new offset amountwill be less than the original offset amount that was determined atblock 1225. At block 1255, the system controller determines whether thenew offset amount meets or exceeds a threshold. If the difference isbelow the threshold, then the system controller determines that thecalibration is complete and leaves the characteristic error valueunchanged at block 1260. If the difference meets or exceeds thethreshold, the method continues to block 1265. At block 1265, the systemcontroller determines an updated characteristic error value based on thenew offset amount. The new offset amount is added to (or subtractedfrom) the first characteristic error value that was computed at block1230 (depending on whether the new characteristic error value ispositive or negative relative to the first characteristic error value).The method then returns to block 1240, and the operations of blocks 1240to 1255 are repeated. This process continues until at block 1255 systemcontroller determines that the new offset amount is below the threshold.

FIG. 13 is flow chart for a method 1300 of determining whether taughtpositions of two robot arms that transfer objects to one another via aload lock are calibrated to one another, according to embodiments of thepresent disclosure. Method 1300 may be performed periodically aftermethod 1200 has been performed. At block 1310 of method 1300, a systemcontroller causes a second or first robot arm (as set forth in FIG. 12)to place a substrate into the load lock using the second or first taughtposition, respectively, optionally as modified by the characteristicerror value. If the first robot arm is on a transfer chamber robot, thenthe second robot arm is on the FI robot and places the substrate usingthe second taught position. If the first robot arm is on the FI robot,then the first robot arm places the substrate using the first taughtposition.

At block 1320, the system controller causes the first or second arm toretrieve the substrate from the load lock using the first or secondtaught position, respectively, optionally as modified by thecharacteristic error value. Either the first taught position or secondtaught position is modified by the characteristic error value (e.g.,offsetting to an inverse of the offset associated with thecharacteristic error value) at block 1310 or the first taught positionor second taught position is modified by the characteristic error valueat block 1320.

At block 1330, the system controller determines, using a local centerfinder at an interface between the load lock and the transfer chamber,whether a new offset is identified. A center of the substrate should bealigned with a center of the pocket on the blade of the robot arm of thetransfer chamber robot and/or with a center of the LCF when thesubstrate is retrieved at block 1320. However, robot error or drift ineither or both of the transfer chamber robot or FI robot may cause thereto be offset.

At block 1340, the system controller determines whether an offset isdetected. If an offset is detected, the method proceeds to block 1350.If no offset is detected, the method continues to block 1345, and thesystem controller determines that the robot arm taught positions areunchanged and that the calibration is still accurate.

At block 1350, the system controller determines that at least one of thefirst taught position of the first robot arm or the second taughtposition of the second robot arm has changed (or that the robot arms'ability to achieve the taught position has changed). At block 1355, thesystem controller determines whether the offset exceeds an offsetthreshold. If the offset is below the offset threshold, the methodcontinues to block 1360 and the current calibration is maintained. Ifthe new offset meets or exceeds the offset threshold, the methodcontinues to block 1365 and a calibration procedure (e.g., thecalibration procedure of method 1200) is initiated.

FIG. 14 is an example computing device 1400 that may operate as a systemcontroller for an electronics processing system, in accordance withembodiments of the present disclosure. The computing device 1400 is amachine within which a set of instructions, for causing the machine toperform any one or more of the methodologies discussed herein, may beexecuted. In alternative embodiments, the machine may be connected(e.g., networked) to other machines in a Local Area Network (LAN), anintranet, an extranet, or the Internet. The machine may operate in thecapacity of a server or a client machine in a client-server networkenvironment, or as a peer machine in a peer-to-peer (or distributed)network environment. The machine may be a personal computer (PC), atablet computer, a web appliance, a server, a network router, switch orbridge, or any machine capable of executing a set of instructions(sequential or otherwise) that specify actions to be taken by thatmachine. Further, while only a single machine is illustrated, the term“machine” shall also be taken to include any collection of machines(e.g., computers) that individually or jointly execute a set (ormultiple sets) of instructions to perform any one or more of themethodologies discussed herein. In an embodiment, computing device 1400corresponds to system controller 132 of FIG. 1. In one embodiment,system controller 132 is a component of computing device 1400.

The example computing device 1400 includes a processing device 1402, amain memory 1404 (e.g., read-only memory (ROM), flash memory, dynamicrandom access memory (DRAM) such as synchronous DRAM (SDRAM) or RambusDRAM (RDRAM), etc.), a static memory 1406 (e.g., flash memory, staticrandom access memory (SRAM), etc.), and a secondary memory (e.g., a datastorage device 1412), which communicate with each other via a bus 1408.

Processing device 1402 represents one or more general-purpose processorssuch as a microprocessor, central processing unit, or the like. Moreparticularly, the processing device 1402 may be a complex instructionset computing (CISC) microprocessor, reduced instruction set computing(RISC) microprocessor, very long instruction word (VLIW) microprocessor,processor implementing other instruction sets, or processorsimplementing a combination of instruction sets. Processing device 1402may also be one or more special-purpose processing devices such as anapplication specific integrated circuit (ASIC), a field programmablegate array (FPGA), a digital signal processor (DSP), network processor,or the like. Processing device 1402 is configured to execute theprocessing logic (instructions 1422) for performing the operationsdiscussed herein. In one embodiment, system controller 132 correspondsto processing device 1402. In embodiments, processing device 1402executes instructions 1426 to implement any of methods 600-1300 inembodiments.

The computing device 1400 may further include a network interface device1408. The computing device 1400 also may include a video display unit1410 (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)),an alphanumeric input device 1412 (e.g., a keyboard), a cursor controldevice 1414 (e.g., a mouse), and a signal generation device 1416 (e.g.,a speaker).

The data storage device 1418 may include a machine-readable storagemedium (or more specifically a computer-readable storage medium) 1428 onwhich is stored one or more sets of instructions 1422 embodying any oneor more of the methodologies or functions described herein. Theinstructions 1422 may also reside, completely or at least partially,within the main memory 1404 and/or within the processing device 1402during execution thereof by the computer system 1400, the main memory1404 and the processing device 1402 also constituting computer-readablestorage media.

The computer-readable storage medium 1428 may also be used to storeinstructions 1426 and/or characteristic error values 1450 as discussedherein above. While the computer-readable storage medium 1428 is shownin an example embodiment to be a single medium, the term“computer-readable storage medium” should be taken to include a singlemedium or multiple media (e.g., a centralized or distributed database,and/or associated caches and servers) that store the one or more sets ofinstructions. The term “computer-readable storage medium” shall also betaken to include any medium other than a carrier wave that is capable ofstoring or encoding a set of instructions for execution by the machineand that cause the machine to perform any one or more of themethodologies described herein. The term “computer-readable storagemedium” shall accordingly be taken to include, but not be limited to,the non-transitory media including solid-state memories, and optical andmagnetic media.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment. Thus, the appearances of the phrase “in oneembodiment” or “in an embodiment” in various places throughout thisspecification are not necessarily all referring to the same embodiment.In addition, the term “or” is intended to mean an inclusive “or” ratherthan an exclusive “or.” When the term “about” or “approximately” is usedherein, this is intended to mean that the nominal value presented isprecise within ±10%.

Although the operations of the methods herein are shown and described ina particular order, the order of operations of each method may bealtered so that certain operations may be performed in an inverse orderso that certain operations may be performed, at least in part,concurrently with other operations. In another embodiment, instructionsor sub-operations of distinct operations may be in an intermittentand/or alternating manner.

The preceding description sets forth numerous specific details such asexamples of specific systems, components, methods, and so forth in orderto provide a good understanding of several embodiments of the presentdisclosure. It will be apparent to one skilled in the art, however, thatat least some embodiments of the present disclosure may be practicedwithout these specific details. In other instances, well-knowncomponents or methods are not described in detail or are presented insimple block diagram format in order to avoid unnecessarily obscuringthe present disclosure. Thus, the specific details set forth are merelyexemplary. Particular implementations may vary from these exemplarydetails and still be contemplated to be within the scope of the presentdisclosure.

It is understood that the above description is intended to beillustrative, and not restrictive. Many other embodiments will beapparent to those of skill in the art upon reading and understanding theabove description. The scope of the disclosure should, therefore, bedetermined with reference to the appended claims, along with the fullscope of equivalents to which such claims are entitled.

What is claimed is:
 1. A method comprising: placing, by a first robot arm in a first one of a factory interface or a transfer chamber, a calibration object into a load lock that separates the factory interface from the transfer chamber, wherein the calibration object is placed into the load lock such that a calibration object center is at a first target location associated with a first taught position of the first robot arm, wherein a first pocket center of a first blade of the first robot arm nominally corresponds to the first target location for the first taught position, and wherein the factory interface, the transfer chamber, and the load lock are components of an electronics processing system; retrieving, by a second robot arm in a second one of the factory interface or the transfer chamber, the calibration object from the load lock onto a second blade of the second robot arm using a second taught position of the second robot arm, wherein a second pocket center of the second blade nominally corresponds to the first target location for the second taught position, and wherein the calibration object center is offset from the second pocket center by a first offset amount after retrieving the calibration object; determining, using a sensor that is in or connected to the second one of the factory interface or the transfer chamber, the first offset amount between the calibration object center and the second pocket center; determining a first characteristic error value that represents a misalignment between the first taught position of the first robot arm and the second taught position of the second robot arm based on the first offset amount; and recording the first characteristic error value in a storage medium, wherein one of the first robot arm or the second robot arm is to use the first characteristic error value to compensate for the misalignment for objects transferred between the first robot arm and the second robot arm via the load lock.
 2. The method of claim 1, wherein the first robot arm is in the transfer chamber, wherein the second robot arm is in the factory interface, wherein the sensor comprises an alignment station in or attached to the factory interface, the method further comprising: placing the calibration object onto the alignment station by the second robot arm.
 3. The method of claim 2, further comprising: placing, by the second robot arm, a substrate to be processed into the load lock using the second taught position of the second robot arm, optionally as modified by the first characteristic error value; retrieving, by the first robot arm, the substrate from the load lock using the first taught position of the first robot arm, optionally as modified by the first characteristic error value, wherein one of the first taught position or the second taught position is modified based on the first characteristic error value to compensate for the first offset amount; determining, using a local center finder at an interface between the load lock and the transfer chamber, whether a new offset exists between a substrate center of the substrate and the first pocket center; responsive to determining that the new offset exists, determining that at least one of the first taught position of the first robot arm or the second taught position of the second robot arm has changed.
 4. The method of claim 3, further comprising: determining whether the new offset exceeds an offset threshold; and responsive to determining that the new offset exceeds the offset threshold, initiating a calibration procedure.
 5. The method of claim 1, further comprising: placing, by the first robot arm, the calibration object into the load lock using the first taught position of the first robot arm, optionally as modified by the first characteristic error value; retrieving, by the second robot arm, the calibration object from the load lock using the second taught position of the second robot arm, optionally as modified by the first characteristic error value, wherein one of the first taught position or the second taught position is modified based on the first characteristic error value to compensate for the first offset amount, and wherein the calibration object center is offset from the second pocket center by a second offset amount after retrieving the calibration object; and determining, using the sensor, the second offset amount between the calibration object center and the second pocket center.
 6. The method of claim 5, further comprising: determining that the second offset amount exceeds an offset threshold; determining an updated characteristic error value based on the second offset amount; and recording the updated characteristic error value in the storage medium.
 7. The method of claim 5, further comprising: determining that the second offset amount is less than an offset threshold; and leaving the first characteristic error value unchanged.
 8. The method of claim 1, wherein the first robot arm is in the factory interface, wherein the second robot arm is in the transfer chamber, wherein the sensor comprises local center finder at an interface between the load lock and the transfer chamber, and wherein the first offset amount between the calibration object center and the second pocket center is determined while the calibration object is removed from the load lock by the second robot arm.
 9. The method of claim 8, further comprising: placing, by the first robot arm, a substrate to be processed into the load lock using the first taught position of the first robot arm, optionally as modified by the first characteristic error value; retrieving, by the second robot arm, the substrate from the load lock using the second taught position, optionally as modified by the first characteristic error value, wherein one of the first taught position or the second taught position is modified based on the first characteristic error value to compensate for the first offset amount; determining, using the local center finder, whether a new offset exists between a substrate center of the substrate and the second pocket center; and responsive to determining that the new offset exists, determining that at least one of the first taught position of the first robot arm or the second taught position of the second robot arm has changed.
 10. The method of claim 9, further comprising: determining whether the new offset exceeds an offset threshold; and responsive to determining that the new offset exceeds the offset threshold, initiating a calibration procedure.
 11. The method of claim 1, further comprising: repeating the placing of the calibration object by the first robot arm, the retrieving of the calibration object by the second robot arm, the determining of the first offset amount, and the determining of the first characteristic error value a plurality of times; determining a standard deviation of the first characteristic error value resulting from the repeating of the placing of the calibration object by the first robot arm, the retrieving of the calibration object by the second robot arm, the determining of the first offset amount, and the determining of the first characteristic error value the plurality of times; and determining an accuracy of a transfer sequence between the first robot arm and the second robot arm via the load lock based on the standard deviation.
 12. The method of claim 1, wherein the calibration object comprises a substrate.
 13. An electronics processing system comprising: a factory interface; a load lock, wherein a first side of the load lock is connected to the factory interface; a transfer chamber connected to a second side of the load lock; and a controller, wherein the controller is to: cause a first robot arm in a first one of the factory interface or the transfer chamber to place a calibration object into the load lock, wherein the calibration object is to be placed into the load lock such that a calibration object center is at a first target location associated with a first taught position of the first robot arm, wherein a first pocket center of a first blade of the first robot arm nominally corresponds to the first target location for the first taught position; cause a second robot arm in a second one of the factory interface or the transfer chamber to retrieve the calibration object from the load lock onto a second blade of the second robot arm using a second taught position of the second robot arm, wherein a second pocket center of the second blade nominally corresponds to the first target location for the second taught position, and wherein the calibration object center is offset from the second pocket center by a first offset amount after retrieving the calibration object; determine, using a sensor that is in or connected to the second one of the factory interface or the transfer chamber, the first offset amount between the calibration object center and the second pocket center; determine a first characteristic error value that represents a misalignment between the first taught position of the first robot arm and the second taught position of the second robot arm based on the first offset amount; and record the first characteristic error value in a storage medium, wherein one of the first robot arm or the second robot arm is to use the first characteristic error value to compensate for the misalignment for objects transferred between the first robot arm and the second robot arm via the load lock.
 14. The electronics processing system of claim 13, wherein the first robot arm is in the transfer chamber, wherein the second robot arm is in the factory interface, wherein the sensor comprises an alignment station in or attached to the factory interface, and wherein the controller is further to: cause the second robot arm to place the calibration object onto the alignment station.
 15. The electronics processing system of claim 14, wherein the controller is further to: cause the second robot arm to place a substrate to be processed into the load lock using the second taught position of the second robot arm, optionally as modified by the first characteristic error value; cause the first robot arm to retrieve the substrate from the load lock using the first taught position of the first robot arm, optionally as modified by the first characteristic error value, wherein one of the first taught position or the second taught position is modified based on the first characteristic error value to compensate for the first offset amount; determine, using a local center finder at an interface between the load lock and the transfer chamber, whether a new offset exists between a substrate center of the substrate and the first pocket center; and responsive to determining that the new offset exists, determine that at least one of the first taught position of the first robot arm or the second taught position of the second robot arm has changed.
 16. The electronics processing system of claim 13, wherein the controller is further to: cause the first robot arm to place the calibration object into the load lock using the first taught position of the first robot arm, optionally as modified by the first characteristic error value; cause the second robot arm to retrieve the calibration object from the load lock using the second taught position of the second robot arm, optionally as modified by the first characteristic error value, wherein one of the first taught position or the second taught position is modified based on the first characteristic error value to compensate for the first offset amount, and wherein the calibration object center is offset from the second pocket center by a second offset amount after retrieving the calibration object; and determine, using the sensor, the second offset amount between the calibration object center and the second pocket center.
 17. The electronics processing system of claim 16, wherein the controller is further to: determine that the second offset amount exceeds an offset threshold; determine an updated characteristic error value based on the second offset amount; and record the updated characteristic error value in the storage medium.
 18. The electronics processing system of claim 13, wherein the first robot arm is in the factory interface, wherein the second robot arm is in the transfer chamber, wherein the sensor comprises local center finder at an interface between the load lock and the transfer chamber, and wherein the first offset amount between the calibration object center and the second pocket center is determined while the calibration object is removed from the load lock by the second robot arm.
 19. The electronics processing system of claim 18, wherein the controller is further to: cause the first robot arm to place a substrate to be processed into the load lock using the first taught position of the first robot arm, optionally as modified by the first characteristic error value; cause the second robot arm to retrieve the substrate from the load lock using the second taught position, optionally as modified by the first characteristic error value, wherein one of the first taught position or the second taught position is modified based on the first characteristic error value to compensate for the first offset amount; determine, using the local center finder, whether a new offset exists between a substrate center of the substrate and the second pocket center; and responsive to determining that the new offset exists, determine that at least one of the first taught position of the first robot arm or the second taught position of the second robot arm has changed.
 20. The electronics processing system of claim 13, wherein the controller is further to: initiate repetition of placing of the calibration object by the first robot arm, retrieving of the calibration object by the second robot arm, determining of the first offset amount, and determining of the first characteristic error value a plurality of times; determine a standard deviation of the first characteristic error value resulting from the repeating of the placing of the calibration object by the first robot arm, the retrieving of the calibration object by the second robot arm, the determining of the first offset amount, and the determining of the first characteristic error value the plurality of times; and determine an accuracy of a transfer sequence between the first robot arm and the second robot arm via the load lock based on the standard deviation.
 21. A non-transitory computer readable medium comprising instructions that, when executed by a processing device, cause the processing device to perform operations comprising: causing a first robot arm in a first one of a factory interface or a transfer chamber to place a calibration object into a load lock that separates the factory interface from the transfer chamber, wherein the calibration object is placed into the load lock such that a calibration object center is at a first target location associated with a first taught position of the first robot arm, wherein a first pocket center of a first blade of the first robot arm nominally corresponds to the first target location for the first taught position, and wherein the factory interface, the transfer chamber, and the load lock are components of an electronics processing system; causing a second robot arm in a second one of the factory interface or the transfer chamber to retrieve the calibration object from the load lock onto a second blade of the second robot arm using a second taught position of the second robot arm, wherein a second pocket center of the second blade nominally corresponds to the first target location for the second taught position, and wherein the calibration object center is offset from the second pocket center by a first offset amount after retrieving the calibration object; determining, using a sensor that is in or connected to the second one of the factory interface or the transfer chamber, the first offset amount between the calibration object center and the second pocket center; determining a first characteristic error value that represents a misalignment between the first taught position of the first robot arm and the second taught position of the second robot arm based on the first offset amount; and recording the first characteristic error value in a storage medium, wherein one of the first robot arm or the second robot arm is to use the first characteristic error value to compensate for the misalignment for objects transferred between the first robot arm and the second robot arm via the load lock. 